99 AC fan running after I turn off engine (1 Viewer)

[509jaykob]

Hopefully someone had this same problem and I haven't looked deep enough in the forums. But the fan for the AC condenser is running after engine shutoff. In winter. Pulled the plug and was clean and dry. To be safe I cleaned with QD cleaner and used some electric grease. Didn't change anything. Pulled fuse 16 and turned off the fan and didn't come back on after inserting the fuse. Assuming it's a relay but not sure which one to check. I have the Toyota service manuals but it isn't incredibly helpful. Really hoping to avoid changing a pressure switch on the AC system. Anyone gone through this issue or know which relay to check? For now I have just unplugged the condenser fan since it's cold enough to not need the AC and I run the floor/defrost mix since it doesn't try to use the AC system. Thank you for any help!

 

[efjayatee]

Trace the wires all the way to the loom. Check for exposed wires or damages

 

[509jaykob]

Sounds so simple. Yet I am so bad a tracing wires. Might have to wait til it's warmer or get access to a shop. I have the fan unplugged as there isn't a need for AC for a few more months. Everything I said reminds me of the short on one of my FICM harnesses had on my Duramax. Just took someone pointing out something so obvious. Thank you

 

[kuelblaz]

Does it eventually turn off by itself? or continue to run until disconnected?
(trying to determine if commanded on for some reason and not shorted wires)

If not shutting off after commanded on, could be different issue all together

 

[509jaykob]

Does it eventually turn off by itself? or continue to run until disconnected?
(trying to determine if commanded on for some reason and not shorted wires)

If not shutting off after commanded on, could be different issue all together

I have let it go for about 5 minutes and it didn't shut off. And disconnecting stops it but it continues to run if I plug it back in. But pulling the fuse turns it off and reinserting the fuse doesn't turn it back on. I'm not the most intelligent with electric connections but I think it essentially "resets" the electrical signal to the fan. When my FICM harness on my duramax had a rubbed wire and created a short it would cut 4 injectors and throw major codes. But after unplugging the harness and plugging it back in, the injectors ran normally and cleared the codes til the wire touched the metal wire guide then it again shut down the same 4 injectors. I simply traced the wire, wrapped the wire to protect it from the guide and then tapped all the wires down to minimize wire movement while the engine is on (duramax forum got me on the right path and directionsto fix). Havent had a problem since. But that's why my brain agrees with the possibility of a shorted wire. The fuse is the FICM harness in this situation and I'll find the short between the fuse and the plug. I could be wrong. But til I get a chance to trace the wire I'm leaving the fan disconnected. Drove it this morning with the fan disconnected and used the defrost/feet setting that keeps the AC off/disengaged and had no issues. I do not believe it's the fan or the fan plug. Looks perfectly fine with no sign of water build-up, rust, oxidation, etc.

 

[darrenk]

My AC fan hasn't worked since I bought my LX. We have +40C in the summer and have never had an issue and the AC runs cool (but would probably be a few degrees cooler if it was running). I have it on my list of things to fix...

 

[509jaykob]

My AC fan hasn't worked since I bought my LX. We have +40C in the summer and have never had an issue and the AC runs cool (but would probably be a few degrees cooler if it was running). I have it on my list of things to fix...

Makes me feel alot better about not worrying about it at the moment. It'll go on the list below rebuilding the alternator lol