No spark, 2013 500 Foreman ES (now not fixed again)

[jeepwm69 7,611]

Another "I have a friend who wants you to look at a Honda" thread.

 

This one belongs to a woman who is caring for my friend's elderly father.  It's a 2013 Foreman ES, exceptionally clean, 900 miles on it, appears to have always been garaged, and hasn't been in the mud much if at all. 

 

I did @Melatv's trick with a jumper wire from battery + to the red/black coil wire, and still no fire.  I told her I'd come back and get it next week to take home to work on it.

 

Since the 2012-2013 Foreman is pretty much an optioned 420, 420 troubleshooting instructions should work for this machine too. 

 

Going to download the FSM now, start reading.  Figured I'd document the process here, as well as get input from the group, so it will hopefully help someone out in the future with the same issue.

[jeepwm69 7,611]

Welp, I've made tentative plans to pick this one up Friday to see if I can figure it out.  I could sure use any input yall might have on this thing.  I've gotten away from the EFI machines because they have so much electrical stuff on them, but this thing is super clean and I'm hoping it won't be a PITA to find out why it doesn't have spark.

First thing I gotta do is get the battery charged up.  It would slowly turn over when I stopped to troubleshoot last week, but I hooked cables to it and it still wouldn't start, so obviously has some issue other than the battery.

[shadetree 5,869]

36 minutes ago, jeepwm69 said:

Welp, I've made tentative plans to pick this one up Friday to see if I can figure it out.  I could sure use any input yall might have on this thing.  I've gotten away from the EFI machines because they have so much electrical stuff on them, but this thing is super clean and I'm hoping it won't be a PITA to find out why it doesn't have spark.

First thing I gotta do is get the battery charged up.  It would slowly turn over when I stopped to troubleshoot last week, but I hooked cables to it and it still wouldn't start, so obviously has some issue other than the battery.

i would start with inspecting all of the wire harness for any chewed damage from mice !.

[jeepwm69 7,611]

1 minute ago, shadetree said:

i would start with inspecting all of the wire harness for any chewed damage from mice !.

 

Yep, it's in a barn shop so that's logical.

 

Has a good strong green neutral light and N showing on the dash.  I was hoping melatv's "jumper wire from battery + to coil" trick would work but it didn't.

[shadetree 5,869]

2 minutes ago, jeepwm69 said:

 

Yep, it's in a barn shop so that's logical.

 

Has a good strong green neutral light and N showing on the dash.  I was hoping melatv's "jumper wire from battery + to coil" trick would work but it didn't.

yeah..inspect for mice damage, and spray some wd-40 into the kill switch. if you have a neutral light, then i would do a good check at reg/rec, as well as the stator harness area for mice damage.

[jeepwm69 7,611]

23 minutes ago, shadetree said:

yeah..inspect for mice damage, and spray some wd-40 into the kill switch. if you have a neutral light, then i would do a good check at reg/rec, as well as the stator harness area for mice damage.

 

The woman's brother put a caltric regulator on it, didn't fix it, so he put the stock one back on.

 

Part interchange shows my Rubicon regulator is the same as this one, so I'll swap mine on and see if it does anything.

 

It's a clean wheeler, but has aftermarket baskets on the racks etc, so gotta get all that crap off and out of the way to see what I'm doing.

[jeepwm69 7,611]

On 11/7/2023 at 1:09 PM, shadetree said:

i would start with inspecting all of the wire harness for any chewed damage from mice !.

That was it.  Several wires had bite marks.  Two were chomped in two.  Spliced/soldered/heat shrinked and it fired right up.

 

Charged her a 12 pack of beer lol.

 

Took me longer to get the rear basket off to get to the wiring than it did to find and fix the problem.

[jeepwm69 7,611]

And, no so fast.

 

Woman called me back, said it again has no spark.

 

This morning I stopped by briefly, tried @Melatv's trick or running a wire from battery + to red/black wire on the coil.  This resulted in the coil hissing and smoking, and of course, a blown fuse after a second or two while I was trying to get the wire off☠️

 

When they were troubleshooting the no spark issue initially, the woman said she replaced the coil, and I will presume they used a china/ebay/amazon replacement since they also put a Caltric voltage regulator on.

 

Plan is to try to find the original coil and put it back on, and if she doesn't still have it, to order one from PSN. 

 

Would a bad coil (possibly an internal short) react this way to Mel's wire trick, or do I have other wiring issues to track down?

[Melatv 792]

Hi Jeep -- the only thing I can think of is the ing. coil the woman replaced -- is that one of the wires on that coil is attached to the metal part of that coil or like you said bad coil.

[jeepwm69 7,611]

I'm going to stop and check it in the next couple of days.  She said she thinks the coil is in her shop, but I haven't had time to look for it yet.  She's out of town at the moment

[jeepwm69 7,611]

So between the ice, family visiting, and just life in general. I’m just now getting back to this one.

I pulled the tank cover off today to get to the coil and removed the aftermarket coil that someone else installed trying to fix the earlier problem and replaced it with a used OEM unit from PSN.

 

I immediately saw the cause of the issue.   The aftermarket coil had a much longer wire on it than an OEM coil, and whomever installed it did not tie it up out-of-the-way, so it was resting on the exhaust,  eventually melting itself to the exhaust and shorting out and blowing the ignition fuse.

 

I was hoping it would be as easy as replacing the call with the OEM unit I bought, but of course nothing is ever that easy.

 

I now have 12 V at the black and red positive coil wire, but still no spark.

 

so my question is, what else should I be looking at? I checked all the wiring connections on the ECU to make sure they were still good and I do not see anything amiss there.

 

if I recall correctly, these coils are hot all of the time and the ECU pulses the negative wire on the coil to power the coil. Is that correct?

 

@retro @Melatv

 

 

 

 

[retro 4,048]

Yeah the PCM/ECM controls the coil and it's a good thing that I looked in the manual because I was thinking it worked differently than what the manual says. Anyway, since you have initial battery voltage at the coil, I think a Peak Voltage test is the next logical thing to do. If I remember right I sent you a homemade PVA a few years ago.... do ya still got that lil' bugger stashed away somewhere? There are two leads coming out of each end (total of 4 leads - they may have alligator clips on them) of the homemade PVA, with one end labelled "to Meter" or something to that effect. If you can find it try this with your multimeter set on DC Volts mode:

 

 

If you don't get a measurement on the first attempt try reversing the PVA leads where they attach to the Green/Yellow and ground, just in case PVA polarity is backwards...

If you still don't measure any pulses perform the same test on the CKP/Pulse gen:

 

 

[jeepwm69 7,611]

I still have the thing in my tool box, never have tried to use it though.

 

Plan is to tinker on the Rubicon engine I’ve had torn down early in the AM, and I’ll dig that thing out of the toolbox and make sure I understand the instructions.

 

Thank you!

[jeepwm69 7,611]

And wouldn't you know I got 1/2 way to work this morning and remembered I was supposed to dig out that peak voltage tool!   I'll try to remember to dig it out after work.   I actually think I know exactly where I put it.

[jeepwm69 7,611]

So I feel like you idiot/ Jeep proofed this thing….lol

 

What does the button on the end do?

[retro 4,048]

4 hours ago, jeepwm69 said:

So I feel like you idiot/ Jeep proofed this thing….lol

 

What does the button on the end do?

 

Aye nah... it's not quite jeep proof'd, it just did not come with any instructions, haha!

 

The button is a momentary switch. It's function and purpose is to drain captured peak voltage from the storage capacitor inside after every test.... it resets the voltage measurement to 0 volts DC so you can repeat PV tests immediately and repeatedly.... rather than wait for the capacitor to drain on it's own.

 

Just make sure that you disconnect one of the PVA leads from the Ignition coil before you depress the reset button, because the coil has battery voltage across it while the Ignition switch is turned on... if you press the reset button while battery voltage is present you might (or might not) let all of the magic smoke out of it, depending on whether I took that sort of usage case into consideration when I put the PVA together? I don't remember.... so to be safe disconnect the lead from the coil before pushing the button.  There is no initial battery voltage present across the Crank position/Pulse generator so you can leave the leads connected while resetting for another test in those cases.

 

By the way, all credits belong to @Melatv, that homemade PVA was made to match his DIY circuit that he posted either here, or possibly on the old VS forum? If I put it together right it should work great.

 

EDIT: Here are the links to @Melatv's DIY PVA threads:

https://www.hondaatvforums.net/threads/make-your-own-test-adapters.120450/

https://www.hondaatvforums.net/threads/peak-voltage-adapter.34406/

 

[jeepwm69 7,611]

Probably be the weekend before I can use it, but I guess you know what you were doing when you sent it to me. Thank you!

[jeepwm69 7,611]

Tried the coil test.  Got 10.3 volts at rest, when cranking voltage dropped to 9ish volts. 
 

so obviously that’s a problem.

where is that ckp sensor?  I got the airbox out but ran out of daylight 

 

[retro 4,048]

Coil voltage should be 12.5+ volts with the key on, so the battery might be too low/dead. I'd charge it up or jump it with a good battery and try again. The CKP (pulse gen) tests should go like so:

 

 

[retro 4,048]

39 minutes ago, retro said:

Coil voltage should be 12.5+ volts with the key on, so the battery might be too low/dead. I'd charge it up or jump it with a good battery and try again.

 

Correct that.... coil voltage should be 12.5+ battery voltage on the Black/Red wire terminal. The voltage on the Yellow/Green terminal of the coil will be less than battery voltage due to resistance in the windings of the coil. So your 10+ volts at rest measurement may be normal...? Anyway, if there is no measured voltage peaks over 100 volts DC between the Yellow/Green and frame ground then the pulse generator/ckp tests are due up next.

[jeepwm69 7,611]

Hooked up + to blue and yellow wire coming off of CKP, negative to green coming off of CKP.  I took the measurement off of the round plug, engine side, so it was unplugged when I did that test. Is that correct?

 

When cranking got 6.2 volts. 
 

got the same thing (6.2V) at the gray connector for the ECU when cranking, with stator/CKP plugged back into main harness

 

 

[retro 4,048]

Yep the CKP sensor peak voltage is good all the way to the ECU. With the coil plugged in there is not 100v or more peak voltage while cranking though, so it possibly has a bad PCM/ECU? I'll have to study the wiring a bit...

[jeepwm69 7,611]

4 hours ago, retro said:

Yep the CKP sensor peak voltage is good all the way to the ECU. With the coil plugged in there is not 100v or more peak voltage while cranking though, so it possibly has a bad PCM/ECU? I'll have to study the wiring a bit...

That’s my concern, when the coil wire melted onto the exhaust it blew the ignition fuse.

 

I replaced the fuse and when I turned the key on the coil started smoking but the ignition fuse did not blow again.  
 

i’m wondering if that fried that ECU

[retro 4,048]

2 hours ago, jeepwm69 said:

i’m wondering if that fried that ECU

 

I'm not buying that... I don't trust the manuals either because there is conflicting info (error) between the two that I am using. So lets back up a bit and ignore the manuals for now...

 

Does the fuel pump run when you turn the key on?

 

With the coil plugged in and the ignition switch on, using your multimeter measure DC volts between the Red/Black coil terminal and ground. There should be battery voltage (12.5v or greater).

 

Then move your Red multimeter lead from the Red/Black terminal to the Green/Yellow terminal on the coil and measure again (black meter lead on ground). Let me know if you measure any voltage.

 

EDIT: FYI, I am using the 2012 Foreman and the 2014-2016 Foreman manuals. I don't trust either of them.

EDIT 2: I am helping my daughter babysit for two babies, nightmare babies actually. I'll try to check in often but if I'm awol for a while that just means I'm preparing a rocket for a low orbit launch..... be back asap.

[jeepwm69 7,611]

19 hours ago, retro said:

 

I'm not buying that... I don't trust the manuals either because there is conflicting info (error) between the two that I am using. So lets back up a bit and ignore the manuals for now...

 

Does the fuel pump run when you turn the key on?

 

With the coil plugged in and the ignition switch on, using your multimeter measure DC volts between the Red/Black coil terminal and ground. There should be battery voltage (12.5v or greater).

 

Then move your Red multimeter lead from the Red/Black terminal to the Green/Yellow terminal on the coil and measure again (black meter lead on ground). Let me know if you measure any voltage.

 

EDIT: FYI, I am using the 2012 Foreman and the 2014-2016 Foreman manuals. I don't trust either of them.

EDIT 2: I am helping my daughter babysit for two babies, nightmare babies actually. I'll try to check in often but if I'm awol for a while that just means I'm preparing a rocket for a low orbit launch..... be back asap.

Fuel pump Clicks on

 

Battery shows 11.7 V at the coil, 12.41 V directly off the battery

 

.26 V on the green yellow