| Simplifying Something From The Factory [message #221654] |
Sun, 08 September 2013 15:18  |
A Hamilto
Messages: 4508
Registered: April 2011
Karma:
|
Senior Member |
|
|
When I had to troubleshoot the heater and AC blower on my 73 Sequoia, I cleaned up that section of the drawing from the MM and posted some aids for the next guy with that problem. I have since pointed a few people with similar problems at the pictures and writeups, so I hope there is some benefit to the community.
When it came up again yesterday, I started looking at the system and came to a conclusion that may or may not be correct.
If battery voltage (0.7VDC lower than alternator voltage) will spin the blower fast enough do we really need the blower relay?
I ask partly because I suspect that no one has tried running the fan on high, and the AC compressor clutch BOTH off the 25A HTR A/C fuse. Given that a lot of places have a 30A fuse and 14AWG wire, is 30A going to create an electrical hazard on the 14AWG wire feeding the fan speed control, or is that too much current for the switch contacts? Is that why GM installed the blower relay?
Here is what I am talking about:
If you disconnect the orange wire, the tan wire and the purple wire from the blower relay and connect them all together, you bypass the blower relay, and you have three fan speeds. HI is a little slower than it was before, and I don't know if even a 30A fuse in the HTR A/C position will be big enough for the fan on HI and the compressor BOTH.
If 30A is enough for both the HI speed blower and the AC compressor, and it does not create an electrical fire hazard, what does the collective brain trust think of removing the blower relay from the circuit?
[Updated on: Sun, 08 September 2013 15:20] Report message to a moderator |
|
|
|
GMCforum
Search
Help
Register
Login
Home
