Electronic Touch Climate Control/ Blower Motor Turn On - Anyone Got This Figured Out?

[6SENSE]

Blower stopped working suddenly back in late summer and have not been able to figure it out. Spent hours troubleshooting today. Blower motor is fine. I have about 4 or 5 control units that I have swapped out over and over but no go with either. I have 5+ of the blower resistor thingys that sit beside the blower motor which the 5wire and 2wire connectors go to. No difference after swapping. Now granted these are all used units that Ive acquired but I find it hard to believe that all of them are bad.
Here is what I learned earlier with the car in the ON position, TEMP setting @ 85, HEAT ON and FAN on HIGH position. 5wire connector at resistor: When plugged in [if I remember right ] all have PWR except for the GRN I think. When unplugged I remember 3 of the 5 wires had power.
2wire plug: (car/heat ON and 5wire plugged in) when unplugged there is PWR at both prongs on resistor but when connector is plugged in there is no power at either wire

Im hoping someone(s) out there has gone through the ins and outs of this system and might have some insight. Im kind of lost here with the limited info Ive been able to find. I was only able to enjoy my new/repaired AC for a few weeks before this problem arose, and now I rarely drive the car because its usually too cold without the blower to move the heat out the vents.

 

[salvageV6]

Don't own one and probably never will but I have a service manual and ten minutes.

Purple is the hot to the blower motor, connected to the motor it should read +12 to a good ground when operating.

Black is the ground and make sure that's to a good ground.

Blower motor test is as follows:

IGN switch to RUN, A/C mode to VENT, blower switch to HI.

Purple wire should read +12 to a good ground on the car, with the two wire connector off.

Purple to the Black wire in the connector should also read +12.

Check those two wires for good connectors, (not melted/corroded) and connections and you should still read about +12 with the blower motor hooked up under those same test conditions accross the two wires purple and black.

Also the light green wire is the PWM signal from the control head to run the fan.

Should be over 10 volts on high and under 7 volts on low.

Read that voltage on the green wire with the connector on and off at the fan area. That seems to be your problem.

Write it all down so you are sure of the results as well.

If you have no voltage on the green wire with the connector off at the fan area then you must check it back at the control head to eliminate the wiring out to the fan area.

No PWM voltage on the light green at the control head would be your problem.

 

[6SENSE]

Thanks Salvage! I will check it out using your instructions as soon as I can, and write results down
Forgot to mention I soldered on some different connectors that were in a bit better shape just in case that had something to do with the problem.

 

[6SENSE]

Okay I am really wanting to drive the car now but with kids its too cold to drive without heat. Still have no idea why blower motor does not kick on. I have 4-5 control units Ive tried swapping in and out. Also have a few blower control modules (the resistor thing next to blower motor).

Here is some data I was finally able to get:

KEY ON, ECON ON (vent), FAN HI
12V+ @ BATTERY

5WIRE PLUG DISCONNECTED, 2WIRE PLUG DISCONNECTED

5WIRE
Red- 12v
Lt Grn/Blk- 12v
Brn- 12v
Ppl- 0
Lt Grn- 0

2WIRE
Ppl- 0
Blk- 0

5WIRE CONNECTED, 2WIRE DISCONNECTED

5WIRE
Red- 12v
Lt Grn/Blk- 12v
Brn- 12v
Ppl- 10v
Lt Grn- 12v

2WIRE
Ppl- 0
Blk- 0

BOTH CONNECTED

5WIRE
Red- 1.7v
Lt Grn/Blk- 10v+
Brn- 12v
Ppl- 10v-
Lt Grn- 12v

2WIRE
Ppl- 0
Blk- 0

If this info means anything to anyone please let me know, starting to get desperate here. I dont know why the Red wire would go from 12v to 1.7v and according to wiring diagram its supposed to be coming from starter fusible link, but then again maybe thats what its supposed to do and thats why I look like this Im better at tuning the car than getting the heat to work, that aint right

ALREADY RAN OUT OF IDEAS, PLEASE HELP

 

[83ttypecooled]

Blower trouble

Hi,
As the man said, the purple wire should be hot. It's 10gauge, right? I remember an intermediate, single wire connector at the back of the engine on these cars that always used to fry, causing no blower. Of course, that was on ,like, an '82 G body.... Long time ago, no access to a wiring diagram. I'd fish around back there and see if....

 

[6SENSE]

Here is a little bit more that I just noticed:

5WIRE CONNECTED, 2WIRE DISCONNECTED

12v @ both spade terminals from the blower control module that the 2wire (Ppl, Blk) connector go to. When connector is attached to them they go to 0v.

Are both terminals from the control module/resistor supposed to be HOT? The black wire on the 2wire connector is a GRD source and tied into the GRD wire that attaches on the blower motor itself. The purple on the 2wire connector is the purple wire that is supposed to feed the blower motor power. If the terminal that the black wire connects to is not supposed to be 12v then maybe when it becomes grounded [when connector plugged in] there is some safety feature that just cuts off power rather than fries everything? Just speculating. Hopefully someone out there can verify whether those terminals are supposed to both be HOT.
Thanks. Man is it cold out there

 

[83ttypecooled]

Hi,
What are the biggest wires on the two connectors going into the blower control unit? There are probably3 or 4. One will be the power wire to the entire system.Another will be a dedicated ground. One will be hot,either at all times, or when the key is in the on position.The other will be ground. I am trying to help you, using only my admittedly faulty memory. Currently, I don't have much else. Good luck!

 

[6SENSE]

Hi,
What are the biggest wires on the two connectors going into the blower control unit? There are probably3 or 4. One will be the power wire to the entire system.Another will be a dedicated ground. One will be hot,either at all times, or when the key is in the on position.The other will be ground. I am trying to help you, using only my admittedly faulty memory. Currently, I don't have much else. Good luck!

Thanks, I appreciate any help I can get at this point. Its got me stumped right now without knowing the ins and outs of this system. The electronic climate control setup definately has a bit more going on than the manual version. If this was the normal manual one I bet I would have already figured it out last year some time.
The biggest wire on the 5wire connector is the RED wire (either 12 or 10gauge) which looking at a diagram from gnttype.org goes to the Starter/fuseable link. So that tells me it should be HOT at all times. The rest of the wires on that plug are approx 16 or 18gauge. Both of the wires on the 2wire connector are 12-10gauge.

 

[6SENSE]

Here is what I have to work with. I grabbed this off of a schematic from gnttype.org that had both manual and electronic setups on it. Its not the easiest to make out. Might have to save to your pics so that you can look closer, or get a magnifying glass up to the screen

 

[6SENSE]

Im starting to think the problem may be at the Red wire on the 5wire plug. If this wire is PWR from the starter/fuseable link then why does it go down to 1.7v? Shouldnt it always stay 12v+ ? I stuck a jumper wire from the Brown over to the Red so that it would have the 12v+ (with the car ON and vent on HI) and the blower DID come on. Im going to need to know for certain if this is where the problem lies and whats going on so I can get that Red wire to stay powered up. I am really hoping that there is someone out there that understands this setup enough to let me know. Is the voltage at the Red PWR wire supposed to drop when the system is on?


P.S. (afterthought) this Red wire that Im talking about shown on the diagram as going to the Starter/fuseable link. Would that mean that there is a single wire and fuseable link dedicated to the blower/heater down at the starter. What I mean is there are two wires coming off the starter with fuseable links on them. Is one of them this same wire that is up at the blower? If so, could there be something faulty with the fuseable link to cause it to do this? I think Im going to remove this wire from the 5pin connector and insert PWR straight from the Battery and see if it too goes down to 1v. I'll post back. Hopefully someone else has some insight, almost feels like Im talking to myself here

 

[83ttypecooled]

Hi,
I spent the last hour going over the diagram you found. Coupling that with your previous voltage charts, I think the problem is indeed with main power to the unit at that red wire,i.e bad connection or some such. If you find such, cut it out and hardwire it!I can't help but think about the trouble we had in the 80s with that one wire connector that was at the rear of the engine. PLEASE follow the wiring back to the starter CAREFULLY. I know, the turbo's back there and not much room. Heat may have played a factor. Good luck, keep us posted!
Dale

 

[BRAD_PADGETT]

I checked in my 85 shop manual and here is the only thing it said about an inoperative blower motor.

1. Cause- Blown fuse-Replace fuse.
2. Cause-Open circuit- Repair circuit between ignition switch, blower switch, and blower motor.
3. Inoperative blower motor switch. Replace faulty switch.
4. Shorted or open blower resistor-Check blower motor resistor.
5. Inoperative motor. Replace motor.
Good luck. It is nice to know by your signature that my goals for my hot air will work. I will be there next month. Brad

 

[salvageV6]

It appears the fusible link A is the double one down by the starter, one lead goes for car power one for the blower motor.

However it also appears that both electronic and standard systems have that pesky connector over by the passenger side near the power (or manual) antenna. It should have a fat red wire in both sides and is probably corroded.

Find that connector which is a 4 cavity one and give it a good cleaning or bypass the red wires with a good splice and I bet the entire system comes to life.

When the blower motor tries to draw current that splice probably isn't giving you any.

A sign that the fusible link A is still good would be if the car runs and drives since that's the main fusible link to power various things like the ECM and CCCI.

A slight chance of a problem would be with the red wire from that connector down to the fusible link splice itself or right at the splice for the two links down by the starter.

I'm betting it's in that 4 cavity connector over beyond the blower motor near the power antenna and hood hinge area.

Good luck.

 

[6SENSE]

Fixed

Thanks for the help guys, I really do appreciate it.
I wish it hadnt taken most of the day but working on it off and on going out and running tests then coming inside to think about it [and warm up] did finally prove to be worth it. Yes, narrowing it down to that Red wire proved to be the right direction. After the last time I posted I went under the car and checked voltage at the starter before and after the fuseable links just for the heck of it. Of course they checked out fine.
Then...... I discovered the Red wire lead down to a certain "4 cavity" connector with 3 wires in it. I just knew that if this was a link between where the wire starts at the starter and where it ends at the blower module that its got to be where the problem lies. Boy was it a b#!@$ to get to, but as soon as I was able to pull it apart I saw how bad it was. Corroded AND burned up. Started removing the fender, then thought about removing the wheel well but got lucky and after moving crap out of the way was able to pull it around to the front of the heater box where I had just enough room to deal with it. I cut the plug off then just went ahead and spliced the wires and all was good
83ttypecooled, you were on the right track. I guess salvageV6 would win the "prize" for pinpointing exactly. Wish I knew that plug existed before. Whats interesting it turns out is that the problem did not have anything to do with the electronic climate control setup. I checked and that plug is on both manual and electric climate control type cars. Good info to know.

 

[salvageV6]

You just started at the wrong end and worked logically back to the problem.

No shame in that, time yes, shame no.

Starting in the middle is difficult on that type system, but works well for most other electrical problems like fuel pump ones, lights etc.

At least it was a cheap fix compared to all the electronic parts it could have been.

I never knew that connector also fed the climate controlled system cars for power, until you posted your test results and additional voltage trouble on the red wire, then I looked it up in da book.

PS: Get that factory service manual on CD or better yet the book form.

 

[Wahoo]

So this connector provides voltage to the digital climate controls in the car?

Maybe thats why mine doesnt light up. Anyone have any pictures of this connector