The fans for the climate control in my 83 XJ6 suddenly stopped blowing this morning while driving. I was thinking it was one of the fuses, but all 4 fuses (50 amp fans, 15 amp for the amplifer as well as the other two) were fine. Using my volt meter, I have 12.8 volts at both sides of the 50 amp fan fuse , BUT I am NOT getting any voltage on the brown/white wire at the resister relay pack. I ran an aux.12 volt wire to the brown/white wire, but the fans still did not come on (using the console mode switch). IF I touch the green/slate wire to the brown/white wire while suppling “my” voltage, the fans run fine. At least, I know the fans are good! Also, I have no power on the brown wire to the amplifier.

I replaced the resister pack, amp and servo with no joy. I should have known these would not work if there was no power on the brown/white wire. But, I am totally confused because the system still will not work when I supply “my” power to the brown/white wire.

After reading hundreds of post and a day of pure frustration, I am gave up!

Any help tremendously appreciated! I’m at a lost of what to do next!

Richard

 

You might have two concurrent problems here.

The 50A fuse for the fans can get hot if there is a poor contact, which can result in the fuseholder plastic melting. Subsequently the prongs of the fuseholder may not grip the fuse firmly so you don’t get the power feed through to the multi-relay. On my car, I had to wire a separate new fuse instead of this one because of this problem. You might be seeing 12V at the end of the fuse but it might not be getting onto the NW wire.

The other fairly likely fault, which would result in missing 12V on the Brown wire, is a malfunctioning microswitch in the main control knob assembly. Without that 12V on the Brown wire, none of the relays in the multi relay block will activate (hence no fans).

The fuse for the AC amp must be 1A. This is important to prevent the amp being damaged in the event of the servo becoming jammed. I am referring to the inline fuse next to the amp connector plug. You mentioned you have 15A fuse for amp, so you need to replace this.

 

Thanks sincerely, Andy for your very important information!

I think you are correct about the 50 AMP fuse not getting the power to the relay pack because I did notice one of the four prongs holding the fuse had melted! I will recheck and run a new wire/fuse if needed!

I think too one of the micro switches has messed up on the mode switch. Question: Is there a positive feed wire to power the mode switch itself? I am wondering if that feed is lost, causing the mode switch not to work (even if the brown/white wire at the relays is ok)? Is there a fuse for it? Where does the wire bundle exit in the car that goes to the mode switch? Is that "bundle" end near the servo on the right side cheek panel? Here's a PIC I found of those wires that go to the mode switch.

Alot of questions, but you are the first that seems to KNOW the system!

Richard

 

The mode switch gets power from fuse #6 of the main fuse panel.

Looking at the circuit diagram, this starts off LG then goes through a connector and becomes G. Then dorect to the mode switch. Do you have the circuit diagram? You will need it to have a chance of troubleshooting this.

The connector in your picture looks like the multi-pin plug to the servo. I cannot remember what the main connector to the Climate Control unit looks like, but it’s not that one (that is internal to the unit)