fan tests ok not coming on low or high, have new relays!

[CREWZIN]

NO, I'm saying I "think" your right and the relays should stay on steadily when the fan is ON. They (relays) are also connected to the PCM so that could be your problem.

[azdave]

Thanks, yea thats what I was thinking. When I took it apart and saw that, according to all the symptoms it sounds like I have a wiring problem. Trouble is going to be figuring out where. It could be anywhere between the PCM and the fan motor. This is going to be fun in this heat. I'm going to look and see if it's hard to look under the PCM to start.

[CREWZIN]

Good luck, try and stay cool.

[edsidders]

looks like hot side of both relay coils feed from Fuse #12 that would be a common possibility.If f#12 gets its power from a auto reset breaker that may be a problem..I'm a new guy here and been messing with my cruiser all day,just found the site ,Real Helpful!!

[Blob]

Azdave, I have a similar problem that I posted last week (Another Overheater), and I still can't get anything to work. You say that you tested both fan speeds, how did you do that? When I jump the connectors in the fan plug it works on one speed.

[joecorvair]

I would check the terminals in the relay socket for a burnt look - you could have a poor connection that is heating up and down like a thermal switch which would make the relay cycle.

[azdave]

I had to wait for 115 outside to let up outside but I have checked a couple more things.

The regular fuses all appear just fine.
I checked the ports for the low speed relay plug in I'm getting 12 v.
I tested the motor again bypassed and both speeds are still fine.
I tested the wires that the fan PLUG INTO under the hood and I got nothing.

[edsidders]

I don't have a Cruiser schematic handy but this acts like there is a current sensor in the fan circut , I just got a error code on mine that indicated a high condition on #1 fan control ckt..Don't really know what that is in Chrysler language..It could be a high resistance or a high current ???

Back to your problem----

From my experience on my wife's BMW there could be a problem in your wiring harness that is causing a overcurrent condition and telling the fan not to run. Like a overload telling the relays to open..Look over the harness for any physical damage(mash or heat) from the fan to the relay box..

[edsidders]

Just got back in from working on mine, found connector for the fan pretty well cooked , guessing the center wire (black) is ground and the other two are low and high...center contact on car side of the harness is melted into the plastic and charred.Kinda hard to see..Too hot outside to continue ..tune in tomorrow for another exciting episode of As-The-Fan-Turns

[azdave]

Looking forward to hearing how it goes for you. Tomorrow before the hot kicks in I'll be in that same place looking at my wires on the car side of the harness. That's the end that I couldn't get any voltage this morning. I didn't have the car up enough to see the condition of the wires. I hope yours is an easy fix.