Honda Foreman 400 No Spark / Intermittent Spark Issue

Good write-up, thanks.

Same thing happened to mine. After a new CDI, coil, and spark plug a new regulator fixed it.

johnchristopherjones said:

As I write this, the issue is solved but I used this forum and others along with a shop manual to repair my 1998 Honda Foreman 400 TRX400. In all my research I didn’t see many definitive solutions so I figured I’d post this in hopes that someone else would find it helpful in the future if faced with the same problem.

In a nutshell , if you are having a no spark / intermittent spark issue then consider replacing the voltage rectifier / regulator. $27 on Amazon and 5 minutes to replace. It’s not always the CDI / ICM.

Now for the details .. went to crank the bike and it wouldn’t start (had been running fine a few hours before). Would turn over strong but wouldn’t start. Didn’t matter if using the electric start or the pull rope , same outcome. The diagnostics began. Fuel checked out fine , battery checked out fine , all switches on and operational , no blown fuses , no burnt or chewed wires , bike was in neutral , etc. All the easy stuff wasn’t it.

Replaced the spark plug , still won’t crank. Pulled the new spark plug and did a spark test .. grounding it to the block external. 90% of the time , no spark. Every once in a while, especially at the instant the starter button was released it would spark once but intermittently. If the starter button was double or triple tapped versus holding constant , it would spark once. But otherwise no spark.

Found a copy of the shop manual which contains the detailed electrical diagrams for the charging and ignition systems. Also provides the continuity and resistance (ohms) indicators for operational components. First check was the ignition coil , checked out fine. Next was the plug wire and boot , all good. Next was the wiring down to the stator and ignition pulse generator , all good. Individually checked all wiring and grounds in the entire harness , all had continuity where they should and path to ground where they should. Checked for operational switches (mainly the ignition and engine kill switches) , all good. Had the battery load tested at Interstate battery , all good. Getting frustrated at this point ...

Checked the online forums and also called a local dealer and internet parts house. Was led that it was most likely the CDI / Ignition Control Module (ICM). Spent $100 on a new OEM unit but nothing changed. Back to square one staring at the electrical diagram.

Consulted the forums again as well as the dealer and parts house. Next suggestion was replacing the ignition coil. If not that, could be the stator or ignition pulse generator. Basically throw parts at it until it’s fixed! But .. on this forum I found one person who said they had replaced their voltage regulator / rectifier and that solved the problem. I figured it was worth a shot. Looking at the electrical diagram I could see one single wire connecting the voltage regulator / rectifier to the ignition system along the path to the CDI / ICM.

Got the new regulator / rectified in this evening and voila the problem is solved. Sparking strong and it fires right up like it once did. Awesome!

Hope this helps someone!

Click to expand...

Having same issue. But no voltage co.ing from stator/ ignition pulse generator? Was you getting vtage from.stator?

johnchristopherjones said:

As I write this, the issue is solved but I used this forum and others along with a shop manual to repair my 1998 Honda Foreman 400 TRX400. In all my research I didn’t see many definitive solutions so I figured I’d post this in hopes that someone else would find it helpful in the future if faced with the same problem.

In a nutshell , if you are having a no spark / intermittent spark issue then consider replacing the voltage rectifier / regulator. $27 on Amazon and 5 minutes to replace. It’s not always the CDI / ICM.

Now for the details .. went to crank the bike and it wouldn’t start (had been running fine a few hours before). Would turn over strong but wouldn’t start. Didn’t matter if using the electric start or the pull rope , same outcome. The diagnostics began. Fuel checked out fine , battery checked out fine , all switches on and operational , no blown fuses , no burnt or chewed wires , bike was in neutral , etc. All the easy stuff wasn’t it.

Replaced the spark plug , still won’t crank. Pulled the new spark plug and did a spark test .. grounding it to the block external. 90% of the time , no spark. Every once in a while, especially at the instant the starter button was released it would spark once but intermittently. If the starter button was double or triple tapped versus holding constant , it would spark once. But otherwise no spark.

Found a copy of the shop manual which contains the detailed electrical diagrams for the charging and ignition systems. Also provides the continuity and resistance (ohms) indicators for operational components. First check was the ignition coil , checked out fine. Next was the plug wire and boot , all good. Next was the wiring down to the stator and ignition pulse generator , all good. Individually checked all wiring and grounds in the entire harness , all had continuity where they should and path to ground where they should. Checked for operational switches (mainly the ignition and engine kill switches) , all good. Had the battery load tested at Interstate battery , all good. Getting frustrated at this point ...

Checked the online forums and also called a local dealer and internet parts house. Was led that it was most likely the CDI / Ignition Control Module (ICM). Spent $100 on a new OEM unit but nothing changed. Back to square one staring at the electrical diagram.

Consulted the forums again as well as the dealer and parts house. Next suggestion was replacing the ignition coil. If not that, could be the stator or ignition pulse generator. Basically throw parts at it until it’s fixed! But .. on this forum I found one person who said they had replaced their voltage regulator / rectifier and that solved the problem. I figured it was worth a shot. Looking at the electrical diagram I could see one single wire connecting the voltage regulator / rectifier to the ignition system along the path to the CDI / ICM.

Got the new regulator / rectified in this evening and voila the problem is solved. Sparking strong and it fires right up like it once did. Awesome!

Hope this helps someone!

Click to expand...

thanks for confirming what i was wondering while studing the wiring dia .

Having same problem here. 1998 Honda Foreman 400. Replaced CDI, Stator, Starter Switch, and the Coil. Intermittent spark and especially sometimes when you release the starter switch. Whats my next move? Voltage Rectifier? What else if there?

johnchristopherjones said:

As I write this, the issue is solved but I used this forum and others along with a shop manual to repair my 1998 Honda Foreman 400 TRX400. In all my research I didn’t see many definitive solutions so I figured I’d post this in hopes that someone else would find it helpful in the future if faced with the same problem.

In a nutshell , if you are having a no spark / intermittent spark issue then consider replacing the voltage rectifier / regulator. $27 on Amazon and 5 minutes to replace. It’s not always the CDI / ICM.

Now for the details .. went to crank the bike and it wouldn’t start (had been running fine a few hours before). Would turn over strong but wouldn’t start. Didn’t matter if using the electric start or the pull rope , same outcome. The diagnostics began. Fuel checked out fine , battery checked out fine , all switches on and operational , no blown fuses , no burnt or chewed wires , bike was in neutral , etc. All the easy stuff wasn’t it.

Replaced the spark plug , still won’t crank. Pulled the new spark plug and did a spark test .. grounding it to the block external. 90% of the time , no spark. Every once in a while, especially at the instant the starter button was released it would spark once but intermittently. If the starter button was double or triple tapped versus holding constant , it would spark once. But otherwise no spark.

Found a copy of the shop manual which contains the detailed electrical diagrams for the charging and ignition systems. Also provides the continuity and resistance (ohms) indicators for operational components. First check was the ignition coil , checked out fine. Next was the plug wire and boot , all good. Next was the wiring down to the stator and ignition pulse generator , all good. Individually checked all wiring and grounds in the entire harness , all had continuity where they should and path to ground where they should. Checked for operational switches (mainly the ignition and engine kill switches) , all good. Had the battery load tested at Interstate battery , all good. Getting frustrated at this point ...

Checked the online forums and also called a local dealer and internet parts house. Was led that it was most likely the CDI / Ignition Control Module (ICM). Spent $100 on a new OEM unit but nothing changed. Back to square one staring at the electrical diagram.

Consulted the forums again as well as the dealer and parts house. Next suggestion was replacing the ignition coil. If not that, could be the stator or ignition pulse generator. Basically throw parts at it until it’s fixed! But .. on this forum I found one person who said they had replaced their voltage regulator / rectifier and that solved the problem. I figured it was worth a shot. Looking at the electrical diagram I could see one single wire connecting the voltage regulator / rectifier to the ignition system along the path to the CDI / ICM.

Got the new regulator / rectified in this evening and voila the problem is solved. Sparking strong and it fires right up like it once did. Awesome!

Hope this helps someone!

Click to expand...

@johnchristopherjones - I must tell you that I signed up for this forum for the sole purpose of saying thank you! I very recently purchased a 2000 Foreman 450 and after a week it was having the exact same symptoms as you described. Thinking I may have been duped, I started searching the service manual and all over the Internet and found an awful lot of advice to do with the Stator, Coil, CDI, Plug, etc., but after everything else tested OK, I luckily came across this post and opted to try the Regulator/Rectifier and boom - good to go!

Thanks again for the info and thanks hondaforum.com - awesome site!

PS - the new Regulator also seems to have fixed my intermittent ES shifting issues as well - bonus!

Andy

what would cause the regulator to fail 2 times in a couple of months ,20 hours of running ?

johnchristopherjones said:

As I write this, the issue is solved but I used this forum and others along with a shop manual to repair my 1998 Honda Foreman 400 TRX400. In all my research I didn’t see many definitive solutions so I figured I’d post this in hopes that someone else would find it helpful in the future if faced with the same problem.

In a nutshell , if you are having a no spark / intermittent spark issue then consider replacing the voltage rectifier / regulator. $27 on Amazon and 5 minutes to replace. It’s not always the CDI / ICM.

Now for the details .. went to crank the bike and it wouldn’t start (had been running fine a few hours before). Would turn over strong but wouldn’t start. Didn’t matter if using the electric start or the pull rope , same outcome. The diagnostics began. Fuel checked out fine , battery checked out fine , all switches on and operational , no blown fuses , no burnt or chewed wires , bike was in neutral , etc. All the easy stuff wasn’t it.

Replaced the spark plug , still won’t crank. Pulled the new spark plug and did a spark test .. grounding it to the block external. 90% of the time , no spark. Every once in a while, especially at the instant the starter button was released it would spark once but intermittently. If the starter button was double or triple tapped versus holding constant , it would spark once. But otherwise no spark.

Found a copy of the shop manual which contains the detailed electrical diagrams for the charging and ignition systems. Also provides the continuity and resistance (ohms) indicators for operational components. First check was the ignition coil , checked out fine. Next was the plug wire and boot , all good. Next was the wiring down to the stator and ignition pulse generator , all good. Individually checked all wiring and grounds in the entire harness , all had continuity where they should and path to ground where they should. Checked for operational switches (mainly the ignition and engine kill switches) , all good. Had the battery load tested at Interstate battery , all good. Getting frustrated at this point ...

Checked the online forums and also called a local dealer and internet parts house. Was led that it was most likely the CDI / Ignition Control Module (ICM). Spent $100 on a new OEM unit but nothing changed. Back to square one staring at the electrical diagram.

Consulted the forums again as well as the dealer and parts house. Next suggestion was replacing the ignition coil. If not that, could be the stator or ignition pulse generator. Basically throw parts at it until it’s fixed! But .. on this forum I found one person who said they had replaced their voltage regulator / rectifier and that solved the problem. I figured it was worth a shot. Looking at the electrical diagram I could see one single wire connecting the voltage regulator / rectifier to the ignition system along the path to the CDI / ICM.

Got the new regulator / rectified in this evening and voila the problem is solved. Sparking strong and it fires right up like it once did. Awesome!

Hope this helps someone!

Click to expand...

Thank you

johnchristopherjones said:

As I write this, the issue is solved but I used this forum and others along with a shop manual to repair my 1998 Honda Foreman 400 TRX400. In all my research I didn’t see many definitive solutions so I figured I’d post this in hopes that someone else would find it helpful in the future if faced with the same problem.

In a nutshell , if you are having a no spark / intermittent spark issue then consider replacing the voltage rectifier / regulator. $27 on Amazon and 5 minutes to replace. It’s not always the CDI / ICM.

Now for the details .. went to crank the bike and it wouldn’t start (had been running fine a few hours before). Would turn over strong but wouldn’t start. Didn’t matter if using the electric start or the pull rope , same outcome. The diagnostics began. Fuel checked out fine , battery checked out fine , all switches on and operational , no blown fuses , no burnt or chewed wires , bike was in neutral , etc. All the easy stuff wasn’t it.

Replaced the spark plug , still won’t crank. Pulled the new spark plug and did a spark test .. grounding it to the block external. 90% of the time , no spark. Every once in a while, especially at the instant the starter button was released it would spark once but intermittently. If the starter button was double or triple tapped versus holding constant , it would spark once. But otherwise no spark.

Found a copy of the shop manual which contains the detailed electrical diagrams for the charging and ignition systems. Also provides the continuity and resistance (ohms) indicators for operational components. First check was the ignition coil , checked out fine. Next was the plug wire and boot , all good. Next was the wiring down to the stator and ignition pulse generator , all good. Individually checked all wiring and grounds in the entire harness , all had continuity where they should and path to ground where they should. Checked for operational switches (mainly the ignition and engine kill switches) , all good. Had the battery load tested at Interstate battery , all good. Getting frustrated at this point ...

Checked the online forums and also called a local dealer and internet parts house. Was led that it was most likely the CDI / Ignition Control Module (ICM). Spent $100 on a new OEM unit but nothing changed. Back to square one staring at the electrical diagram.

Consulted the forums again as well as the dealer and parts house. Next suggestion was replacing the ignition coil. If not that, could be the stator or ignition pulse generator. Basically throw parts at it until it’s fixed! But .. on this forum I found one person who said they had replaced their voltage regulator / rectifier and that solved the problem. I figured it was worth a shot. Looking at the electrical diagram I could see one single wire connecting the voltage regulator / rectifier to the ignition system along the path to the CDI / ICM.

Got the new regulator / rectified in this evening and voila the problem is solved. Sparking strong and it fires right up like it once did. Awesome!

Hope this helps someone!

Click to expand...

Got the exact same problem except starter stays engaged. Only way to stop is disconnect battery.

johnchristopherjones said:

As I write this, the issue is solved but I used this forum and others along with a shop manual to repair my 1998 Honda Foreman 400 TRX400. In all my research I didn’t see many definitive solutions so I figured I’d post this in hopes that someone else would find it helpful in the future if faced with the same problem.

In a nutshell , if you are having a no spark / intermittent spark issue then consider replacing the voltage rectifier / regulator. $27 on Amazon and 5 minutes to replace. It’s not always the CDI / ICM.

Now for the details .. went to crank the bike and it wouldn’t start (had been running fine a few hours before). Would turn over strong but wouldn’t start. Didn’t matter if using the electric start or the pull rope , same outcome. The diagnostics began. Fuel checked out fine , battery checked out fine , all switches on and operational , no blown fuses , no burnt or chewed wires , bike was in neutral , etc. All the easy stuff wasn’t it.

Replaced the spark plug , still won’t crank. Pulled the new spark plug and did a spark test .. grounding it to the block external. 90% of the time , no spark. Every once in a while, especially at the instant the starter button was released it would spark once but intermittently. If the starter button was double or triple tapped versus holding constant , it would spark once. But otherwise no spark.

Found a copy of the shop manual which contains the detailed electrical diagrams for the charging and ignition systems. Also provides the continuity and resistance (ohms) indicators for operational components. First check was the ignition coil , checked out fine. Next was the plug wire and boot , all good. Next was the wiring down to the stator and ignition pulse generator , all good. Individually checked all wiring and grounds in the entire harness , all had continuity where they should and path to ground where they should. Checked for operational switches (mainly the ignition and engine kill switches) , all good. Had the battery load tested at Interstate battery , all good. Getting frustrated at this point ...

Checked the online forums and also called a local dealer and internet parts house. Was led that it was most likely the CDI / Ignition Control Module (ICM). Spent $100 on a new OEM unit but nothing changed. Back to square one staring at the electrical diagram.

Consulted the forums again as well as the dealer and parts house. Next suggestion was replacing the ignition coil. If not that, could be the stator or ignition pulse generator. Basically throw parts at it until it’s fixed! But .. on this forum I found one person who said they had replaced their voltage regulator / rectifier and that solved the problem. I figured it was worth a shot. Looking at the electrical diagram I could see one single wire connecting the voltage regulator / rectifier to the ignition system along the path to the CDI / ICM.

Got the new regulator / rectified in this evening and voila the problem is solved. Sparking strong and it fires right up like it once did. Awesome!

Hope this helps someone!

Click to expand...

I got to say this helped me tremendously been having a **** fit with this thing lol the fact you explained where holding the start would not fire and as soon as you let of or beginning it would fire thanks brother man!!

Basically just change every part until it starts firing?

johnchristopherjones said:

As I write this, the issue is solved but I used this forum and others along with a shop manual to repair my 1998 Honda Foreman 400 TRX400. In all my research I didn’t see many definitive solutions so I figured I’d post this in hopes that someone else would find it helpful in the future if faced with the same problem.

In a nutshell , if you are having a no spark / intermittent spark issue then consider replacing the voltage rectifier / regulator. $27 on Amazon and 5 minutes to replace. It’s not always the CDI / ICM.

Now for the details .. went to crank the bike and it wouldn’t start (had been running fine a few hours before). Would turn over strong but wouldn’t start. Didn’t matter if using the electric start or the pull rope , same outcome. The diagnostics began. Fuel checked out fine , battery checked out fine , all switches on and operational , no blown fuses , no burnt or chewed wires , bike was in neutral , etc. All the easy stuff wasn’t it.

Replaced the spark plug , still won’t crank. Pulled the new spark plug and did a spark test .. grounding it to the block external. 90% of the time , no spark. Every once in a while, especially at the instant the starter button was released it would spark once but intermittently. If the starter button was double or triple tapped versus holding constant , it would spark once. But otherwise no spark.

Found a copy of the shop manual which contains the detailed electrical diagrams for the charging and ignition systems. Also provides the continuity and resistance (ohms) indicators for operational components. First check was the ignition coil , checked out fine. Next was the plug wire and boot , all good. Next was the wiring down to the stator and ignition pulse generator , all good. Individually checked all wiring and grounds in the entire harness , all had continuity where they should and path to ground where they should. Checked for operational switches (mainly the ignition and engine kill switches) , all good. Had the battery load tested at Interstate battery , all good. Getting frustrated at this point ...

Checked the online forums and also called a local dealer and internet parts house. Was led that it was most likely the CDI / Ignition Control Module (ICM). Spent $100 on a new OEM unit but nothing changed. Back to square one staring at the electrical diagram.

Consulted the forums again as well as the dealer and parts house. Next suggestion was replacing the ignition coil. If not that, could be the stator or ignition pulse generator. Basically throw parts at it until it’s fixed! But .. on this forum I found one person who said they had replaced their voltage regulator / rectifier and that solved the problem. I figured it was worth a shot. Looking at the electrical diagram I could see one single wire connecting the voltage regulator / rectifier to the ignition system along the path to the CDI / ICM.

Got the new regulator / rectified in this evening and voila the problem is solved. Sparking strong and it fires right up like it once did. Awesome!

Hope this helps someone!

Click to expand...

Similar issues...but different outcome.

I own 2 identical quads, except 1 red and 1 bluegrey.
Red wouldn't start 1 day. Didn't have time to deal with it. Sent to dealer. 3 months later and $1000 dollars they replaced the plug, cap, cable, coil, ICM. Was running but no good when I picked it up. They said low compression was the fault. Loaded it. Brought it home. Wouldn't start. Just rolled it off into the garage. Did nothing for 1 year. Recenly tried several things. Swapped old CDI into running grey quad and fires up no problem. All 3 CDI, both original and new dealer replaced unit make red grey quad run no problem.
Checked all ignition harness wiring and plugs for continuity. All good. Checked resistand on pulse generator. Off by 1 or 2 ohms. Ordered and replaced. No go. Still no spark. Swaped coil cable and cap assy from blue and red quads. Grey quad runs, red still no spark. Figured not getting induction in stater to induce current in pulse generator. Check continuity and resistance on all 3 charging yellow wires. All identical. Swapped regulator/governor from running grey with no spark Red. Grey quad no start. Red quad has spark now but no start. Same symptoms as Matt1228. Figured vale timing. Pulled out because ignition timing is not adjustable. Cam sproket really close to timing mark. It can't be the problem.

I can swap the carbs, but it feels and sound like a timing issue. Started to think of similar issues i had in the past on my wifes minivan and a mercury outboard years apart a long while ago. In both cases, the flywheel sheered the key on the shaft and was off detonating at random times, causing backfire that made the flywheel to slip into a new position, where sometimes it was close enough to run then suddenly just stop and backfire. On the van the backfire ended up causing #2 cylinder rollers to jump out and cause all kinds of new issues that weren't related to the slipping flywheel causing additional TS nightmares.
Anyways, have you seen sheared keys on Honda quads happen causing these symptoms before?

Lastly i put in a new spark plug, even though the dealer had replaced it. Seen them faulty new and easy diag for $6.
Pull the crank and get 1 or 2 sparks only.
Hit starter and 1 to 2 sparks then nothing, followed by no spark when cranking until starter stopped then 1 or 2 sparks has momentum slows to a stop.
Seen similar issues with equipment where a Murphy switch will kill the engine if it doesn't have engine oil pressure or temp too high or other impending catastrophic conditions. Of course the Murphy's bypass switch must be pressed while cranking for a few seconds until oil P climbs within operational limits.
Are these quads equipped with a safety cutout? For oil P or engine oil temp? Is it possible that the cutout switch only shuts ignition off after a few turns of the ignition.
Another alternative.
Is it possible that that the starter system draw too much amps during cranking somehow affecting the stator coils capacity to induce a voltage after a few seconds? I did crank the starter using a seperate battery with jumpers and still have 2 sparks at beginning and 2 more after cranking stops....