2006 Wrangler 2.4 wiring question

[Geok]

Does anyone know if the radiator fan fuse relay attached to the radiator shroud is grounded BEHIND (in front of really) the shroud?
I don't have this additional wiring on mine, and am having trouble getting a new fan to work, and it may be as simple as no ground. I assumed the black wire in the harness from the PDC went back to main ground, but thought I'd ask if anyone knows (or can take a pic, etc).

Thanks!

 

[Wildman]

Does anyone know if the radiator fan fuse relay attached to the radiator shroud is grounded BEHIND (in front of really) the shroud?
I don't have this additional wiring on mine, and am having trouble getting a new fan to work, and it may be as simple as no ground. I assumed the black wire in the harness from the PDC went back to main ground, but thought I'd ask if anyone knows (or can take a pic, etc).

Thanks!

View attachment 598519

You can download your FSM (Factory Service Manual) from this link in the Resource area.

STICKY Thread 'Jeep Wrangler TJ Factory Service Manuals (FSM) & Technical Documentation'

Apr 9, 2017

This post is for TJ documentation like Factory Service Manuals Etc..
A while back I was able to find the FSM for my 2006 TJ. I decided to look at the same website I have used to download FMS to see if I can find others. I hit the jackpot so I am sharing :beer-toast1:

Please if there are any issues or they are inaccurate let me know.

Thanks @UpperMI for the additional 2002 manuals

• JeepNWilly
• fsm maintenance manual owners manual pdf service manual shop manual
• Replies: 269
• Forum: TJ Resources

• 
• 
• 

 

[AaronPaul]

Some TJ models, particularly 2003-2006 (I think) models with electric fans, had their relay ground connected directly to the shroud.
Earlier models may have grounded differently, but the fan relay always requires a ground source to function.
If your relay is missing its original ground, adding a solid chassis ground to the relay body should solve the issue.

 

[Geok]

Some TJ models, particularly 2003-2006 (I think) models with electric fans, had their relay ground connected directly to the shroud.
Earlier models may have grounded differently, but the fan relay always requires a ground source to function.
If your relay is missing its original ground, adding a solid chassis ground to the relay body should solve the issue.

Thanks AaronPaul, for the reply. I looked at the above linked schematic for body grounds, and G190 is the ground for the fan assembly. That's next to the right headlight. There is a BK/DG wire from the PDC harness that grounds to G190, and then attaches to the fan harness. I verified that there is continuity to ground from the harness, so it looks like it's working. I was hoping for something simple, but now I'm thinking there is a signal issue from the ECM

Back to the drawing board.

I guess I can just disconnect the low speed relay EVERY-TIME I drive until I solve this.

 

[AaronPaul]

Thanks AaronPaul, for the reply. I looked at the above linked schematic for body grounds, and G190 is the ground for the fan assembly. That's next to the right headlight. There is a BK/DG wire from the PDC harness that grounds to G190, and then attaches to the fan harness. I verified that there is continuity to ground from the harness, so it looks like it's working. I was hoping for something simple, but now I'm thinking there is a signal issue from the ECM

Back to the drawing board.

I guess I can just disconnect the low speed relay EVERY-TIME I drive until I solve this.

If you suspect the issue might be with the ECM (Engine Control Module) not sending the correct signal, it's important to consider a few other potential causes:
-Fan Relay
-Fan Control Circuit
-Coolant Temperature Sensor (CTS)

If the relay is receiving power and functioning, but the fan is still not operating, the ECM signal is a likely culprit. Additionally, recheck any sensor wiring, particularly the coolant temperature sensor, as it can sometimes be the source of the issue.

 

[Geok]

Relays tested fine
Coolant temp switch was replaced (I didn't get resistance on it when tested. The new one does)
I don't see a fan control unit on the schematic
I don't get continuity on pin 86 Low speed relay socket when A/C is switched on. That makes me think it's either the PCM or the cable between the PCM and Power Distribution Center. But I'm happy to be wrong, because I don't want to replace the PCM

 

[Geok]

I added some refrigerant to the system today, and the fan kicked on with A/C. I guess it needed to get up to pressure before the PCM would ground the low speed fan.
I didn't get it to go to high speed yesterday running it, but maybe I just didn't get up to temp? It was slightly past mid-way on gauge (210F). I'll try again today after work.

 

[Geok]

We got a winner! Fan comes on with A/C once charged, so needs pressure before PCM will send signal. And, comes on about a little over 210F on Temp gauge.