Hi Y'all - getting colder here in Southern Arizona (yeah, I know, 40F is absolutely freezing here). Took the kitty out for dinner last night and all we got from the climate control was cold air blowing. At that point I turned it off and endured the "I told you about this car" glare from the spousal unit.

Spent some time this AM inspecting, reading, doing some troubleshooting and so on. Here's where we are:

Background: this is the same car in which I just replaced the fusebox I busted during the install of the WhiteXKR remote top controller.

1) Checked the heater water pump fuse in the box - good.
2) Swapped #1 relay with another. Still no heat.
3) Performed climate control diagnostic (the push AUTO and RECIRC buttons, turn on ignition, hit face button, etc) - no codes.
4) Read TSB regarding flushing the coolant due to poor heater performance, performed the initial test - set system on HI, keep RPM at 2000 and check heater performance.
4a) Turns out at this point I got nice heat coming from the ducts, don't know the exact temp though. TSB says that's a pass (probably).
4b) Found that if I let the RPM go back to idle, no more heat. Climate control still set on HI.
4c) If I set climate control to 91F (just under HI), the AC comes on (Normal) but I lose all heat, even at 2000RPM.

Up until 4c, I was suspecting the heater water pump, thinking the higher RPMs were forcing enough hot coolant through the heater core even without the pump working. But now I'm not so sure.

Any thoughts on further diagnosis?

Thank,
Scott

 

My money is on the heater pump. It's English Pounds so safe bet !

 

I found no voltage is getting to the heater pump. By jumpering the #1 relay in the engine fuse box I get normal heater operation.

I see no voltage at either side of the relay coil.

From looking at the circuit diagram I believe the one side floats until grounded by the AC control module and the other side (circle with 41 II) should be at +12V.

Looking further ... ideas welcome.

 

Check fuse #3 (a 5A fuse) in the engine compartment fusebox. I'll bet your fog lights are also out.

 

Yup. After tracing it out that was my suspicion as well. Right on the money.

I made that "*** U ME ption" that all the fuses in the replacement box were good. Doh!

I pulled all the other fuses and checked them just to be sure - all OK.

Now, what I don't know is if that fuse was blown when I got the box or if it blew in my vehicle. I suppose time will tell.

Maybe it was a prostitron. You know, the odd electron that runs around blowing fuses ...

Thanks Steve, much appreciated.

 

Glad you got it working. But I think I get my money back since no heat due to pump not working. You get your share cos pump ok but no electron flow.
Merry Christmas !

 

All your money is on its way back to you as we speak. Your thought kept me on the right track!

Muchas gracias, Feliz Navidad y Prospero Ano Nuevo!

60 miles from Mexico