Electrical Question
#1
11-08-2011, 12:54 PM
Electrical Question
Having issues with fan only coming on when the A/C is turned on. I performed a test of the #1 socket on the Fuse relay panel on the 3 fan relays as the Haynes manual says. I'm getting a reading on the #3 relay but nothing on the #1 or #2. It doesnt say anything about what to do after. I'm getting +5v to the new ECS. Is this telling me the wiring between the PCM and ECS are good?
I also jumped the pins under the dash and the fans came on. I'm stumped and man I hate electrical crap.
I also jumped the pins under the dash and the fans came on. I'm stumped and man I hate electrical crap.
#2
11-08-2011, 01:07 PM
I have a Haynes manual and it's pretty specific on how to check the relays and what to do in both cases.
You check for continuity between terminals 1 and 4, without power there should be none. The book gives an example of how to tell with terminals are which and I believe they are labeled on the unit itself. Then, taking a jumper wire of sorts, apply power to terminal 5 and ground terminal 2 and then you SHOULD get continuity between 1 and 4. IF NOT, then you change the relay. It is the same method for all relays.
I did this method when I first got my car and found 2 bad relays. Just be careful when messing with the jumper wires.
Also, the 5v reading you're getting on the ECS means it is getting sufficient voltage and the wiring is ok. But, the sensor may still be bad and giving false readings. You have to check signal voltage to be sure of that I think.
You check for continuity between terminals 1 and 4, without power there should be none. The book gives an example of how to tell with terminals are which and I believe they are labeled on the unit itself. Then, taking a jumper wire of sorts, apply power to terminal 5 and ground terminal 2 and then you SHOULD get continuity between 1 and 4. IF NOT, then you change the relay. It is the same method for all relays.
I did this method when I first got my car and found 2 bad relays. Just be careful when messing with the jumper wires.
Also, the 5v reading you're getting on the ECS means it is getting sufficient voltage and the wiring is ok. But, the sensor may still be bad and giving false readings. You have to check signal voltage to be sure of that I think.
#3
11-12-2011, 10:09 PM
Well, Looks like the problem is between the ECT and the PMC there is no resistance between in the yellowwire between the 2 but the black wire is good. I'll try a jumper tomorrow then figure out where the problem is.
#4
11-13-2011, 01:34 AM
I made a post earlier but it isn't showing up now for some reason...? So, Ill post it all again.
When flushing the system, are you taking out the block coolant drain plug located on the driver side of the block? Take it out to fully drain all the coolant. Then, flush water through the system a few times until it looks clean. After that, put the plug back in and fill the system with water and the flushing solution. Drive the car around for a good while with heat turned on full to fully flush everything. Bring the car back and let it idle for awhile. Turn it off and let it cool down. Then, go back out and drain it all again removing the plug etc. Flush more water through it a few times to help ensure all the flush solution is out. Put the plug back in and use water a few more times (added assurance). Then make sure everything is drained properly and refill with 50/50 coolant. NOT DEXCOOL since a lot of ppl say it helps to eat gaskets and cause more problems. Refill with 50/50 coolant.
Bleed the lines using the bleeder screws that are on the coolant hoses. Slightly loosen them until air begins to seep out. Keep them open until all the air is out and a steady stream of coolant begins to run out. People prefer to have the vehicle on an incline to help. Then after bleeding tighten the screws and go for another drive to circulate the coolant. Bring it back and bleed again. Keep bleeding like this until all air is out of the system.
I also think I saw on another thread how you were talking about taking it to a shop or getting several different shops to give opinions? You didn't want to spend the money on a shop. So, the solution to that would be instead of spending the $85 to have a shop look at it go online to a vendor like Moates and buy an aldl cable of your own so you can hook your laptop up to the port under your dash and run your own scans. It's fairly simple once you read up on it. The cable can be a usb so it hooks to your computer, make sure you get the correct connector. You have an OBD1 pcm with an OBD2 connector. There are quite a few FREE SCANNING SOFTWARE programs available once you search for them and they work wonders. Better to have it in the long run to look at the data and codes yourself rather then paying every time.
***EDIT***
Looked up my old posts, I was referring to the wrong thread. Disregard. But, the cable info may still be useful to you.
lol
When flushing the system, are you taking out the block coolant drain plug located on the driver side of the block? Take it out to fully drain all the coolant. Then, flush water through the system a few times until it looks clean. After that, put the plug back in and fill the system with water and the flushing solution. Drive the car around for a good while with heat turned on full to fully flush everything. Bring the car back and let it idle for awhile. Turn it off and let it cool down. Then, go back out and drain it all again removing the plug etc. Flush more water through it a few times to help ensure all the flush solution is out. Put the plug back in and use water a few more times (added assurance). Then make sure everything is drained properly and refill with 50/50 coolant. NOT DEXCOOL since a lot of ppl say it helps to eat gaskets and cause more problems. Refill with 50/50 coolant.
Bleed the lines using the bleeder screws that are on the coolant hoses. Slightly loosen them until air begins to seep out. Keep them open until all the air is out and a steady stream of coolant begins to run out. People prefer to have the vehicle on an incline to help. Then after bleeding tighten the screws and go for another drive to circulate the coolant. Bring it back and bleed again. Keep bleeding like this until all air is out of the system.
I also think I saw on another thread how you were talking about taking it to a shop or getting several different shops to give opinions? You didn't want to spend the money on a shop. So, the solution to that would be instead of spending the $85 to have a shop look at it go online to a vendor like Moates and buy an aldl cable of your own so you can hook your laptop up to the port under your dash and run your own scans. It's fairly simple once you read up on it. The cable can be a usb so it hooks to your computer, make sure you get the correct connector. You have an OBD1 pcm with an OBD2 connector. There are quite a few FREE SCANNING SOFTWARE programs available once you search for them and they work wonders. Better to have it in the long run to look at the data and codes yourself rather then paying every time.
***EDIT***
Looked up my old posts, I was referring to the wrong thread. Disregard. But, the cable info may still be useful to you.
lol
Last edited by JGuy07; 11-13-2011 at 01:38 AM.
#6
11-14-2011, 08:27 AM
Thanks
test your system, number 12 and 20 on the list here 4th Gen LT1 F-Body Tech Aids
Last edited by JackBlack95; 11-14-2011 at 08:32 AM.
#7
11-14-2011, 08:32 AM
Thanks
I made a post earlier but it isn't showing up now for some reason...? So, Ill post it all again.
When flushing the system, are you taking out the block coolant drain plug located on the driver side of the block? Take it out to fully drain all the coolant. Then, flush water through the system a few times until it looks clean. After that, put the plug back in and fill the system with water and the flushing solution. Drive the car around for a good while with heat turned on full to fully flush everything. Bring the car back and let it idle for awhile. Turn it off and let it cool down. Then, go back out and drain it all again removing the plug etc. Flush more water through it a few times to help ensure all the flush solution is out. Put the plug back in and use water a few more times (added assurance). Then make sure everything is drained properly and refill with 50/50 coolant. NOT DEXCOOL since a lot of ppl say it helps to eat gaskets and cause more problems. Refill with 50/50 coolant.
Bleed the lines using the bleeder screws that are on the coolant hoses. Slightly loosen them until air begins to seep out. Keep them open until all the air is out and a steady stream of coolant begins to run out. People prefer to have the vehicle on an incline to help. Then after bleeding tighten the screws and go for another drive to circulate the coolant. Bring it back and bleed again. Keep bleeding like this until all air is out of the system.
I also think I saw on another thread how you were talking about taking it to a shop or getting several different shops to give opinions? You didn't want to spend the money on a shop. So, the solution to that would be instead of spending the $85 to have a shop look at it go online to a vendor like Moates and buy an aldl cable of your own so you can hook your laptop up to the port under your dash and run your own scans. It's fairly simple once you read up on it. The cable can be a usb so it hooks to your computer, make sure you get the correct connector. You have an OBD1 pcm with an OBD2 connector. There are quite a few FREE SCANNING SOFTWARE programs available once you search for them and they work wonders. Better to have it in the long run to look at the data and codes yourself rather then paying every time.
***EDIT***
Looked up my old posts, I was referring to the wrong thread. Disregard. But, the cable info may still be useful to you. lol
When flushing the system, are you taking out the block coolant drain plug located on the driver side of the block? Take it out to fully drain all the coolant. Then, flush water through the system a few times until it looks clean. After that, put the plug back in and fill the system with water and the flushing solution. Drive the car around for a good while with heat turned on full to fully flush everything. Bring the car back and let it idle for awhile. Turn it off and let it cool down. Then, go back out and drain it all again removing the plug etc. Flush more water through it a few times to help ensure all the flush solution is out. Put the plug back in and use water a few more times (added assurance). Then make sure everything is drained properly and refill with 50/50 coolant. NOT DEXCOOL since a lot of ppl say it helps to eat gaskets and cause more problems. Refill with 50/50 coolant.
Bleed the lines using the bleeder screws that are on the coolant hoses. Slightly loosen them until air begins to seep out. Keep them open until all the air is out and a steady stream of coolant begins to run out. People prefer to have the vehicle on an incline to help. Then after bleeding tighten the screws and go for another drive to circulate the coolant. Bring it back and bleed again. Keep bleeding like this until all air is out of the system.
I also think I saw on another thread how you were talking about taking it to a shop or getting several different shops to give opinions? You didn't want to spend the money on a shop. So, the solution to that would be instead of spending the $85 to have a shop look at it go online to a vendor like Moates and buy an aldl cable of your own so you can hook your laptop up to the port under your dash and run your own scans. It's fairly simple once you read up on it. The cable can be a usb so it hooks to your computer, make sure you get the correct connector. You have an OBD1 pcm with an OBD2 connector. There are quite a few FREE SCANNING SOFTWARE programs available once you search for them and they work wonders. Better to have it in the long run to look at the data and codes yourself rather then paying every time.
***EDIT***
Looked up my old posts, I was referring to the wrong thread. Disregard. But, the cable info may still be useful to you.
lol
#8
11-15-2011, 07:48 AM
Allright. I put in the new ECT and ran the car at idle. It got to 3/4 up on the temp gauge and no fan kicked on. I got in the car and reved it up then the fans kicked on. I turned the car off let it sit 15 minutes then started it back up let it run and the fans kicked on by themselves. They were kicking on at 3/4 and turning off at 1/2. Seems a bit high but I guess the only way to verify the temp is to purchase a scanner or laptop cable. I have to go to work so I won't be able to run the car up the road but fingers are crossed.
For those of you keeping score at home I just bought a new ECT at O'reilly and it looks like that was the problem.
For those of you keeping score at home I just bought a new ECT at O'reilly and it looks like that was the problem.
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