Hvac blend doors and high speed blower relay ground

[John Moore]

Hey guys, can anyone tell me if the HVAC blend doors and the high speed blower relay share the same ground?

My high speed does not work and I tried replacing the relay and verified the hot circuit is good.

None of the blend doors respond. I’ve also replaced the HVAC control panel, same issue.

I’m assuming they all share a ground. Hope so at least!!

 

[GoToGuy]

Are you using the OE service manual? The manual has the diagrams and drawings of all ground locations. All circuits.
Does the fan work in all speeds or is one or more speeds not working? There are three flapper type valves.

 

[John Moore]

Are you using the OE service manual? The manual has the diagrams and drawings of all ground locations. All circuits.
Does the fan work in all speeds or is one or more speeds not working? There are three flapper type valves.

My OE Manuals are in storage. The blower speeds work expect the High speed.

Temp, mode, and re-circ doors do not work.

AC compressor switch works, along with switching it to defrost the compressor will come on.

 

[GoToGuy]

The pdf are available here free in the forum. Have you checked the fan resister, if a section is bad you lose 1 or more speed settings.

 

[AK49BWL]

According to my diagrams, all the actuators, the high relay, AND blower motor share the same ground point, but it looks to be possible they are using separate terminals and the one for the actuators and relay has become disconnected.

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[John Moore]

According to my diagrams, all the actuators, the high relay, AND blower motor share the same ground point, but it looks to be possible they are using separate terminals and the one for the actuators and relay has become disconnected.

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This is encouraging news!!!!!! thank you so much, i'll check it out tomorrow.

 

[xXxPARAGONxXx]

According to my diagrams, all the actuators, the high relay, AND blower motor share the same ground point, but it looks to be possible they are using separate terminals and the one for the actuators and relay has become disconnected.

You must be registered for see images attach

S244 is a 5-wire splice. There's no terminals at that splice. Instead, there should be a splice crimp.

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There will be a ring terminal at G202. The ring terminal will be crimped onto two black wires. One black wire comes from the blower motor, and the other black wire comes from the splice (S244).

Checking continuity on each ground circuit with a DMM is a good start for troubleshooting.

Key off.
Select continuity on the DMM.
Disconnect all the following connectors: (1) high blower relay, (2) blower motor, (3) front mode door motor, (4) front temperature door motor, and (5) recirculation door motor.
Place red lead of the DMM on G202.
Place black lead of the DMM on the BLK terminal of each connector to test for continuity, one at a time. Is there continuity on each? If so, then your ground circuit is good. Troubleshoot elsewhere.

 

[AK49BWL]

S244 is a 5-wire splice. There's no terminals at that splice. Instead, there should be a splice crimp. ......

If you'll notice in the diagram, the blower motor ground does not go to S244 therefore I said nothing about S244. I was referring to the ring terminals, of which there will likely be two, one of which may have come loose.

Checking the grounds with a multimeter would be the next step after verifying the grounds are in fact where they should be mounted.

 

[John Moore]

Update:

FIXED!

I found the ground location on the right side of the dash, saw the two wires. Followed the smaller one and found it was broken way in the back. Spliced it and everything works again. Very enjoyable!

Thanks again guys