03 Expy XLT Climate Controls Issue

[kilobyte]

After attaching some RCA cables to the existing radio for a new amp install, the climate controls are no longer working on an 03 XLT (manual controls). We get no blower motor on any of the 4 settings. The AC light doesn't engage when pressed, but the rear defrost does. I can hear the vacuum doors changing when I change from floor to upper on the vents.

We have checked fuses 5, 13 and 116, plus relay 6. We took the dash off again and double checked all the connectors to the controls and checked the wires at the connectors. We are all good there.

It seems as though there isn't power except for the rear defrost. The rear system is in-op at this point also. Both were working before. I am guessing there may be an upstream connection/relay of some type for both systems that we may have affected, but don't know where to look for that.

Any help appreciated.

 

[bedrck46]

Have attached some prints that may help also check fuses 11,14 and 33

 

[kilobyte]

bedrck46, thanks much for the diagrams.

Its finally warm enough today to do some tests.

I found some test procedures to test the manual climate system. These may help someone else having similar issues.
View attachment Manual Climate test proc1.pdf
View attachment Manual Climate test proc2.pdf
View attachment Manual Climate test proc34.pdf

For me, Step 6 - runs the blower.

Step 7 - I have a resistance of about 67Ohms, so that tells me I have a problem with circuit 57 (bk). I don't see that on any of the wiring diagrams, but do see 57 paired with several other circuits, such as 57 12(bk), 57 14(bk), 57 20(bk), etc. I assume BK means black (ground) for these circuits.

Does anyone know if there is a specific circuit 57?
From one of the diagrams from Bedrck46, I think this is probably 57 20(bk) but want to check if anyone has any more details on that before I dig in further.

thanks,

 

[bedrck46]

The solid black wire is a ground wire is it possible that when you did the RCA cables that you may have disconnected a ground or broken the ground wire

the # 57 is the circuit number the numbers 12,14,20 etc that appear after #57 is the wire gauge and if you suspect 57-20 you are looking at a small gauge wire and it wouldn't take much to either pull it loose or to break it from the ground commection

 

[bedrck46]

prints attached
10-4 is all the grounds that go to G200
151-16 shows the location of G200

if you suspect the you lost a ground then you could go to the connector that you suspect and hook a jumper on circuit 57 Blk wire from that connector to ground and see if the circuit works or you could use an ohm meter to check the circuit

 

[kilobyte]

bedrck46 - thanks for the prints, I found my missing ground today and i'm fixed.

thanks again,

 

[bedrck46]

glad you found the problem where was the ground that was missing??

 

[kilobyte]

It was on one of the dash controls, the electrical connector above the vacuum connector on the multi-selector switch.

 

[bedrck46]

thanks