Anyone have 03-06 wiring diagrams?

[oddball]

Looking to do the electric fan swap on my '02, but would prefer to use the factory fan from the later models. I've got half a plan in my head, but need the wiring diagrams for the fan since it has a bunch of leads. As long as it's not looking for a variable speed input this should be relatively easy.

So, anyone have the wiring diagram book from 03 to 06? Just need scans of a few pages. Unfortunately, the service manual that's online doesn't have the info I need.

Bonus: I'll take pics and post a step-by-step when it works.

 

[owlman]

I looked in my diagrams and this seems to be the only connector for the cooling fan motor. Since you say there are a bunch of leads, what other connectors do you need?

 

[joegr]

Yes, there are just four wires, two for power, and two for control.

"As long as it's not looking for a variable speed input this should be relatively easy."
Sorry, but it is.

I do have the 04 wiring diagrams. What specifically do you need?

 

[oddball]

I looked in my diagrams and this seems to be the only connector for the cooling fan motor. Since you say there are a bunch of leads, what other connectors do you need?

Thanks for the pic! For example, check out the upper LH side of this one - there's two connectors. Looks like the one with four large gauge wires like the picture, and another connector with two wires.
Where's pin 3 going? Any indication what kind of signal that is? Joegr makes me fear that's a PWM input of some kind. That would suck.

"As long as it's not looking for a variable speed input this should be relatively easy."
Sorry, but it is.

(in best Shatner voice while shaking fists) LIIIINNNNCCOOOOOOOOOOOOLLNN!!!!!

I do have the 04 wiring diagrams. What specifically do you need?

From the pic above, looks like two hots, one ground, one speed control. Two fused hots makes me scratch my head, though.
Well, what I thought would be incredibly simple runs something like:
The actuator for the hydraulic fan pump has two wires: 12V and a signal wire that runs to the PCM. When high speed is needed, the PCM grounds the signal wire. Seems to me this would be a *perfect* way to signal a relay to drive a fan. The PCM is already monitoring when the fan is required (temp and/or a/c), no need to mess with the :q:q:q:qty aftermarket fan controls.
So if the factory electric fans had really simple control like the Mark VIII's, then this would work. I'd like the clean install of a factory piece, too. Looks like the mount ears and the aux pump mounts are the same as the hydraulic fan. To simple to actually work, huh?

 

[joegr]

I think they went to a single connector in 05 or 06. My 06 is one 4-pin connector.

My 04 is two 2-pin connectors.

The big one is Power and ground, a 60 A fused circuit that it live all the time. It powers the fan motor.

The smaller one is control.
Pin 1 is the control signal from/to the PCM. I don't know what kind of signaling it uses, but it seems to be two way as the PCM has error codes for the cooling fan turning or not.
Pin 2 is a just power for the microprocessor that is built into the fan motor. It is switched such that it is only powered when the key is in the run or start position. The fuse is 15A, but that circuit feeds other things too. I suspect that the fan microprocessor needs less than one amp.

(Don't let the multiple pins in the picture fool you, it's two pins for power and two for ground because of the high current involved. It's still just two wires.

 

[oddball]

Ah-ha! That makes sense. I was wondering about the differences between the 03-04 and 05-06 fans. Different connectors, same wires sounds like. Silly. Separate power circuit for built-in logic also makes sense.

Do the diagrams give any hint about the signaling from the PCM? My '02 shows the real simple internal logic when it's just a switch or similar. Or, if you're feeling really generous, could you probe that line? Is the fan actually multi-speed, or just slow/fast?

Thanks!

 

[joegr]

Ah-ha! That makes sense. I was wondering about the differences between the 03-04 and 05-06 fans. Different connectors, same wires sounds like. Silly. Separate power circuit for built-in logic also makes sense.

Do the diagrams give any hint about the signaling from the PCM? My '02 shows the real simple internal logic when it's just a switch or similar. Or, if you're feeling really generous, could you probe that line? Is the fan actually multi-speed, or just slow/fast?

Thanks!

The diagrams show a switch to ground inside the PCM, but I'm 95% sure that's not how it works.

Another member on here once tried to do exactly what you are trying to do. As I recall, they were never able to control the fan speed. I think they were able to have it either off or at full speed, with nothing in between. If you search, you may be able to find the thread about it. (I couldn't.)

The fan is continuously variable speed, it's not just a simple on, off, low, med, high sort of a thing.

If you give up on the OEM fan, then this might help.
http://www.lincolnvscadillac.com/Lincoln-cadillac-archive/topic/68306-1.html

I don't mind probing the fan signals, but with my current home project backlog, it may be years before I can get to it...