Craby, Psycho and Pete, thanks. Going out work on it now. Will let you know what happens. I really do appreciate your knowledge.

Bob

 

Craby, Pete and Psycho: Did all of what you suggested below:

pull the under hood fuse box and see if theres any damage on the underside. pull the wires off the power junction box(red plastic box on the passenger side fenderwell) clean and check for damage. pull the ground wires off the ground junction next to the power junction. check and clean them as well. it may be worth checking the ground wires on the front of the block on the diver side as well. No damage on the underside hood fuse box. Cleaned and saw no damage to wires on/in the power junction box. Checked the ground wires on the front of the block on driver side and all is right.

I believe the sensor on the water pump has to call for the fans at a preprogrammed temp (160-180) before the relay comes on.
I don't know if there is a way to fool the computer into thinking that the temp is high enough for the relay to come on. (see next item)

Unplug the connector at the ECT sensor and short the two wires going back to the PCM to each other. This will make the PCM think that the engine is running red hot, and the PCM will signal the fan relays to turn on the fans. I did this and the fans DID NOT come on, so I applied a ground connection under the hood to the relays and that activated the fans, both high and low speed.

Could it be that the computer is not making the ground connection to the relays since the dk blue and dk green wires go to the computer where they need to be connected to a ground?


Any further ideas? Never been stumped by a vehicle....but this is my first real computerized car! Bring back the good old days! If this wasn't such a great car to drive....... My wife's going to make this convertible into a front yard planter box!

 

most systems on the 4th gens are ground activated and positive fused. it seems you are missing a ground somewhere. time to check all your grounds. you have one on the passenger side of the block in front of the starter, you have one at the front of the block on the passenger side under the tensioner. there are also a couple grounds on the inside the car on each side shown as g200 and g201. i would suggest you pick up a factory service manual for your yr camaro. ill look a little closer in my 93 book and see whats in comon for these three if i can.

 

THANKS CRABY for the info and the schematic. I just checked the grounds and are all solid and undisturbed with no corrosion. I am using the CHILTON GM CAMARO/FIREBIRD 1993-98 REPAIR MANUAL.

 

your going to have to pick up a volt/ohm meter and start checking the ground wires for continuity past the connector. there may be fused links on the grounds although i have not really had reason to look so keep your eyes open for any as you test the wires. anyways try and track the ground from failing sytems back and see what you find.

 

Craby,

Did everything all have suggested including your last ones. Checked ALL grounds, all good. What I found is that all the hot wires are going to the computer but the computer appears not to be making the appropriate grounds to the A/C, the Air Pump and the Fans. Again, bypassed the computer and each of the components work. Am I wrong in thinking it is as simple as replacing the computer??

Thanks again for all help.

Bob

 

Although rare, as it should happen if the battery is connected backwards, it could be possible that a driver circuit inside the computer (quad driver) that provideds ground to relays got blown out. There is no fix for that except to replace the computer. While you are checking out the grounds, like Craby described, also make sure the computer is making good contact to ground.

 

OK Pete! Got me there, what is a Quad Driver? This is his wife right now. He is out at the car.

Arlyn

 

Quad driver is elctronic circuit used in computers to actually interface with hardware outside the computer. It is part of the mother board and not easily fixable.

Here some good reading to put you to sleep:
http://www.batauto.com/articles/quaddriver.shtml

 

Thanks Pete. Bob is not a computer guru and this is the first time I had heard of that term related to a vehicle. I'll let him know. You may hear him yell from here! ;-)