Overheating Problem w/ NO CODES
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Joined: Apr 2019
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Overheating Problem w/ NO CODES
Back in November I received a 2004 Trailblazer LS to use as a work vehicle. When I received it, the AC Controls were messed up (the driver side temp control was broken off). I drove it for roughly 3 weeks before ordering a used control unit from eBay. Once I installed that, the AC went to working great. However, another problem started. The car overheated. Since then I have tried everything I can think of and apparently everything anyone else can think of. I have changed nearly every part of the cooling system but have yet to correct the problem. Here's what I have done so far:
2 NEW radiators
3 NEW radiator caps
NEW water pump
NEW fan clutch
NEW hose (both to the overflow tank and from radiator to the engine)
2 NEW Thermostats (I know the on currently installed works - I boiled it)
NEW overflow/reservoir tank
Installed 2 - 8 inch electric fans on my AC condensor
Ran liquid aluminum to fix the head gasket
Flushed the radiator
Ran Blue Devil to fix head gasket
I think that I have narrowed the problem down to my fan clutch not running properly. However, I don't think it's the fan clutch itself. I think it's not being told what to do. Initially when I would COLD start the engine, the fan wouldn't engage. I read another thread and the guy said he'd had problems with the factory harness and he removed it and hardwired the 5 wires together and that fixed his problem. I did that. The fan clutch is now directly connected to the wiring harness. When I COLD start my engine now, the fan engages on high for about 5 seconds and slows. When I overheat, I used to be able to stop the fan with my hand. After hardwiring it, I no longer can stop it, but it's also not running on high. All my water runs into the overflow and stays there. I was told I need to run a manual dash switch and turn it on when I was driving myself so it always ran on high. I have not been able to accomplish this. I've searched everywhere and can't find anyone that can tell me how to bypass the relays. Oh, and yes, the relays ARE good. I checked those out. I've also attempted to manually force the fan to engage on high by running a 10 amp jumper between the number 2 and number 4 relay pin port. That didn't work even with I ran my engine idle at 2K rpm for over 5 minutes.
My OBD is only showing one code C0040 (front wheel speed sensor circuit). I can't figure this out.
2 NEW radiators
3 NEW radiator caps
NEW water pump
NEW fan clutch
NEW hose (both to the overflow tank and from radiator to the engine)
2 NEW Thermostats (I know the on currently installed works - I boiled it)
NEW overflow/reservoir tank
Installed 2 - 8 inch electric fans on my AC condensor
Ran liquid aluminum to fix the head gasket
Flushed the radiator
Ran Blue Devil to fix head gasket
I think that I have narrowed the problem down to my fan clutch not running properly. However, I don't think it's the fan clutch itself. I think it's not being told what to do. Initially when I would COLD start the engine, the fan wouldn't engage. I read another thread and the guy said he'd had problems with the factory harness and he removed it and hardwired the 5 wires together and that fixed his problem. I did that. The fan clutch is now directly connected to the wiring harness. When I COLD start my engine now, the fan engages on high for about 5 seconds and slows. When I overheat, I used to be able to stop the fan with my hand. After hardwiring it, I no longer can stop it, but it's also not running on high. All my water runs into the overflow and stays there. I was told I need to run a manual dash switch and turn it on when I was driving myself so it always ran on high. I have not been able to accomplish this. I've searched everywhere and can't find anyone that can tell me how to bypass the relays. Oh, and yes, the relays ARE good. I checked those out. I've also attempted to manually force the fan to engage on high by running a 10 amp jumper between the number 2 and number 4 relay pin port. That didn't work even with I ran my engine idle at 2K rpm for over 5 minutes.
My OBD is only showing one code C0040 (front wheel speed sensor circuit). I can't figure this out.