A/C unit is blowing warm air

Tiny
ASEMASTER6371
  • EXPERT
That was a red/black wire correct?

Roy
Was this
answer
helpful?
Yes
No
Tuesday, August 11th, 2020 AT 3:52 PM
Tiny
BWILKINSON05
  • MEMBER
Roy,
Correct, pin 14 which has a red wire with black line.
Bret
Was this
answer
helpful?
Yes
No
Tuesday, August 11th, 2020 AT 4:00 PM
Tiny
ASEMASTER6371
  • EXPERT
Does not make sense. You have replaced the ECM and it still has no power to that pin. Without that power the control side of the relay will not work.

Roy
Was this
answer
helpful?
Yes
No
Tuesday, August 11th, 2020 AT 4:45 PM
Tiny
BWILKINSON05
  • MEMBER
Roy,

I agree. This is why I reconsidered the climate control module. I'm not pressing this just thinking through the possibility - if the climate control module is not sending enough power to the low side switch/sensor, I have 5v and per the manual I should have 12v, there is not enough power to send a signal back to CCM to the ECM to the high side sensor back to the ECM to trip the relay and then power the A/C compressor clutch.
Would it work to jump a line from the battery to the low side sensor?
Bret
Was this
answer
helpful?
Yes
No
Tuesday, August 11th, 2020 AT 5:10 PM
Tiny
BWILKINSON05
  • MEMBER
Roy,
One other thought, I believe when the compressor relay is jumped it's bypasses the climate control computer and powers the compressor clutch.
Bret
Was this
answer
helpful?
Yes
No
Tuesday, August 11th, 2020 AT 5:16 PM
Tiny
ASEMASTER6371
  • EXPERT
No, the power for that wire has nothing to do with the climate control module. It is supplied by the ECM to the pressure sensor.

Yes, correct, jumping 30 and 87 sends direct power to the compressor without the control side of the relay grounding.

Roy
Was this
answer
helpful?
Yes
No
Tuesday, August 11th, 2020 AT 5:29 PM
Tiny
BWILKINSON05
  • MEMBER
Roy,

Any suggestions on additional tests?
Here's a recap of my test methods, with key in on position:
When I tested the low side sensor - using a multi-meter I touched the red lead to the paperclip in connector and black lead to the battery negative post.
Same with ECM pin 14 test - inserted paperclip in back of harness, plugged harness into ECM, red to paperclip, black to battery negative post
Same process with high side sensor.
Was my test correct?
Bret
Was this
answer
helpful?
Yes
No
Wednesday, August 12th, 2020 AT 8:06 AM
Tiny
ASEMASTER6371
  • EXPERT
Yes, but the issue is nothing at pin 14.

This leads me back to the ECM again. Let me look for any other information.

Roy
Was this
answer
helpful?
Yes
No
Wednesday, August 12th, 2020 AT 8:11 AM
Tiny
BWILKINSON05
  • MEMBER
Roy,
How do I test the power going into the ECM? See July 11th email with schematic. I believe that's the issue. Pin 14 is line from the ECM to the high side sensor. If you look at the schematic, I would like to test the line from the CCM to the ECM, it's the grey line. I believe I need to remove CCM and back probe the grey line.
Bret
Was this
answer
helpful?
Yes
No
Wednesday, August 12th, 2020 AT 8:22 AM
Tiny
ASEMASTER6371
  • EXPERT
If there was no power to the ECM, you would have many other issues and a ton of codes.

The gray wire you told me had 5 volts as it should. Why do you want to check it again? That along with the red/black need 5 volts.

Roy
Was this
answer
helpful?
Yes
No
Wednesday, August 12th, 2020 AT 8:50 AM
Tiny
BWILKINSON05
  • MEMBER
Roy,

Agree. I am referencing the white line in the schematic from 7/11 from the climate control module to the ECM. I would like to confirm that line has power with a back probe test.
Should the low side sensor have 5V or 12V?
Bret
Was this
answer
helpful?
Yes
No
Wednesday, August 12th, 2020 AT 10:55 AM
Tiny
ASEMASTER6371
  • EXPERT
You are off track here. The issue is the red/black wire. Neither of those wires have any effect on power to that wire.

Roy
Was this
answer
helpful?
Yes
No
Wednesday, August 12th, 2020 AT 11:06 AM
Tiny
BWILKINSON05
  • MEMBER
Roy,
10-4. What is the power source to the red/black wire?
Bret
Was this
answer
helpful?
Yes
No
Wednesday, August 12th, 2020 AT 11:46 AM
Tiny
ASEMASTER6371
  • EXPERT
Again, the ECM.

Roy
Was this
answer
helpful?
Yes
No
Wednesday, August 12th, 2020 AT 11:49 AM
Tiny
BWILKINSON05
  • MEMBER
Roy,
10-4. Should I contact fs1inc and ask for input?
Bret
Was this
answer
helpful?
Yes
No
Wednesday, August 12th, 2020 AT 11:59 AM
Tiny
ASEMASTER6371
  • EXPERT
Yes, see if they can get you some information.

Roy
Was this
answer
helpful?
Yes
No
Wednesday, August 12th, 2020 AT 12:06 PM
Tiny
BWILKINSON05
  • MEMBER
Roy,

For testing purposes only, what should the voltage be at the white wire exiting the climate control module connecting to SP205 then to the ECM? What is the SP205? Also, do you have a schematic of the climate control module you can send?
Thank you,
Bret
Was this
answer
helpful?
Yes
No
Thursday, August 13th, 2020 AT 3:09 PM
Tiny
ASEMASTER6371
  • EXPERT
I attached the diagram with the white wire. It is serial data. There is no voltage. It is a multiplexing signal.

Roy
Was this
answer
helpful?
Yes
No
Thursday, August 13th, 2020 AT 3:23 PM
Tiny
BWILKINSON05
  • MEMBER
Roy,
What should the readings be at pin #'s: 58 and 43?
Bret
Was this
answer
helpful?
Yes
No
Thursday, August 13th, 2020 AT 8:17 PM
Tiny
ASEMASTER6371
  • EXPERT
58 is the serial data line I told you about.

43 is the wire from the control side of the relay. It will have 12 volts there unless the ECM grounds that wire. Then it will be 0.

Roy
Was this
answer
helpful?
Yes
No
Friday, August 14th, 2020 AT 4:24 AM

Please login or register to post a reply.

Sponsored links