Novak Conversions Jeep Wrangler TJ engine mounts

P0443 code (I'm at a loss)

TJustin

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Long post warning, hopefully someone can help! TIA

Flash back to earlier today. I am out at a local mountainous area where I go to test new Jeep modifications. Yesterday I made suspension changes and wanted to see if I had any clearance issues. While out there, the CEL came on. Drove to the local O'Reilly's. The scanner pulled P0443 code. 2 likely issues were the evap canister purge valve, and gas cap. Initially I ruled out the gas cap, and purchased the purge valve and went home. Installed it and disconnected the battery for 1 hr. Reconnected the battery, and started it, CEL is off. Took the family for a drive and it came back on. Back to O'Reilly's I went and purchased a gas cap. Installed the gas cap, disconnected the battery again. While waiting for the computer to reset I checked the evap lines and connectors for cracks. Connected the battery again and CEL stayed off until the 2nd time I started it, and it came on again.

Pulled the #11 fuse in the glove box, and it was blown. Put another 10 amp fuse in, with the new solenoid in, and it immediately blew it and turned the CEL back on. Put the original solenoid back in, put in a brand new fuse, started it and blew another fuse.

Checked schematics, and found that the circuit for the #11 fuse is for the Auto Trans torque converter solenoid, AC compressor, and the Evap purge valve. The Jeep has no AC, and has a manual. I checked the fuse block under the hood, and do not see relays in those slots. I've narrowed it down to electrical, but electrical is my weakness.

What is the likelihood that I bought a faulty purge valve? What can be done to check the Jeep's wiring? Did the TJ's all have the same harnesses regardless of factory options? Is it possible that the circuits for the AC or torque converter are shorted?

Any help is appreciated.
 
Long post warning, hopefully someone can help! TIA

Flash back to earlier today. I am out at a local mountainous area where I go to test new Jeep modifications. Yesterday I made suspension changes and wanted to see if I had any clearance issues. While out there, the CEL came on. Drove to the local O'Reilly's. The scanner pulled P0443 code. 2 likely issues were the evap canister purge valve, and gas cap. Initially I ruled out the gas cap, and purchased the purge valve and went home. Installed it and disconnected the battery for 1 hr. Reconnected the battery, and started it, CEL is off. Took the family for a drive and it came back on. Back to O'Reilly's I went and purchased a gas cap. Installed the gas cap, disconnected the battery again. While waiting for the computer to reset I checked the evap lines and connectors for cracks. Connected the battery again and CEL stayed off until the 2nd time I started it, and it came on again.

Pulled the #11 fuse in the glove box, and it was blown. Put another 10 amp fuse in, with the new solenoid in, and it immediately blew it and turned the CEL back on. Put the original solenoid back in, put in a brand new fuse, started it and blew another fuse.

Checked schematics, and found that the circuit for the #11 fuse is for the Auto Trans torque converter solenoid, AC compressor, and the Evap purge valve. The Jeep has no AC, and has a manual. I checked the fuse block under the hood, and do not see relays in those slots. I've narrowed it down to electrical, but electrical is my weakness.

What is the likelihood that I bought a faulty purge valve? What can be done to check the Jeep's wiring? Did the TJ's all have the same harnesses regardless of factory options? Is it possible that the circuits for the AC or torque converter are shorted?

Any help is appreciated.

May have nothing to do with the Purge solenoid and sounds more like a dead short. There are numerous harness plugs that are not used with no AC and manual trans so it's a good place to start, Get some good light and start under the hood looking for burnt, chafed or chewed harness.
 
Get some good light and start under the hood looking for burnt, chafed or chewed harness.

Exactly where I would start looking as well.

I've found when problems can't seem to be solved, it almost always ends up being damage to some wiring, often times that is very, very hard to spot unless you start digging.
 
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In your description, you missed one other circuit tied to fuse 11.......Daytime Running Lamp Module. Not sure if your Jeep is equipped with that, but another circuit to trace and see if there is a short.
 

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first thing i would do is verify you have 12volts at the b+ circuit. Unplug the connector at the purge solenoid, ignition on verify you have 12 volts at circuit f12 (red/light green wire).
The control circuit (ground) is controlled by the PCM. What you can do is ohm out the ground circuit end to end to check resistance.
There is also connector c110 you may wish to check and verify there is no corrosion.

1599394048570.png


1599393902597.png
 
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In your description, you missed one other circuit tied to fuse 11.......Daytime Running Lamp Module. Not sure if your Jeep is equipped with that, but another circuit to trace and see if there is a short.

Thank you. You are right. It does not have daytime running lights either.
 
I had that code and was told it was a gas cap. Replaced it then was told it was electrical or canister. Was looking under the hood and saw a slightly disconected hose. I got lucky
 
If it’s blowing the fuse as soon as you put the fuse in, it sounds like the wire that supplies battery voltage to that fuse and ultimately the purge valve is chafing or rubbing against a ground.

Disconnect the battery positive cable. Get a DVOM and set to ohms. Put one probe on the positive supply for that purge valve (you might need to probe the fuse slot itself if the short is before the fuse) and one probe on the negative battery terminal. If the wire is grounding or damaged you will see an ohms reading. If it’s not and is ok you should see “OL”
 
Sorry, I didn't see the part where you are blowing the fuse. Sounds like you have a short to ground in the B+ circuit. I would start checking the harness from the solenoid back to the fuse box.
 
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If you do not have 12volts @ the purge with the ignition on, you need to start back tracing the circuit to the fuse box.

Okay. I’m blowing the fuse immediately upon turning the ignition on. Doesn’t require the solenoid to be plugged in. Along the firewall I don’t see anywhere that has chafed or have holes in it where it would have been rubbed raw. Still searching but this is after 1/2 hr looking at things.

checked the connector (c110 I believe) located by the abs tray. No corrosion there.

Tried the multimeter idea above and got readings but not confident that I was using it properly.
 
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Unplug connector c106, and see if the fuse still blows. If it still pops you have a short between the fuse box and the connector. If it doesn't blow you have a short between c106 and the purge solenoid.
I'm sorry about the diagram not really giving a good location for c106. looks to be close to the fuse box itself.
If it is between the connector and the purge solenoid....you can always just string a new circuit instead of searching for the short.
1599492614239.png
 
The other thing you can try. Take your DMM setting to ohm. black lead to ground. unplug the purge solenoid.
Remove the 10 amp fuse from the fuse block, probe the non b+ side of the fuse. you should show O.L. on the DMM. If you show any resistance, the circuit is grounding somewhere.
 
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The other thing you can try. Take your DMM setting to ohm. black lead to ground. unplug the purge solenoid.
Remove the 10 amp fuse from the fuse block, probe the non b+ side of the fuse. you should show O.L. on the DMM. If you show any resistance, the circuit is grounding somewhere.

I think I’ve found the culprit. I pinched a wire when installing my transfer case after re-clocking it last Friday. It is an unused wire, so I expect it to be for the torque converter solenoid. Either way it is pinched between the trans tail housing and transfer case.

I’m about to pull the transfer case back out and to fix the wiring. Once fixed, I’ll see if it still blows fuses.

A05BC147-6BDC-4F19-8F28-4F45350F3413.jpeg
 
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Novak Conversions Jeep Wrangler TJ engine mounts