Fan wiring diagram
Fan wiring diagram any suggestions on where i could find wiring diagrams on my 93 T/A? I am trying to figure out why my fans will not turn on by themselves. I replaced the relays, and the senson in the waterpump and the one right under the head(sending unit for gauge cluster). I know my fans function because i have a SLP designed (home made) manual fan swith and the high and the low speed both work. I do own a Hayes Book for my car, but my buddy still has it from us getting his 98 Z-28 back on the road. I would go pick it up but the weather in my area has kinda kept me in my house. So any suggestions on websites would be greatly appreciated.
another thing that i had a question about is that i have read that people say that the 93 only has one speed for the fans (only two relays). Mine on the other had has both a high and a low speed. When i connected the manual switch i can click it one way and only on comes on. When i click it the other way both fans engage at a higher speed. I have 3 relays in the electrical box under the hood. Any suggestions that might help me. Because I am lost big time on this one.
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The 93 fans are one speed. We have to fans, a primary and secondary. The 95+(maybe 94+) are dual speed fans.
Have you tried turning your AC on? This will force both fans on. Are you sure you didn't unhook the factory wiring when you wired your manual switch?
Have you tried turning your AC on? This will force both fans on. Are you sure you didn't unhook the factory wiring when you wired your manual switch?
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From: Decatur, TN (N-W of Athens)
If they're single speed, why the triple wired plugs? Usually that's for twin speeds. One ground, 2 power. Unless I'm REALLY not remembering the plug right, but I just unplugged it a couple weeks back, so it's pretty fresh in my mind.
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If it has 3 relays, its 'high' 'low' fans.
I have the exact same problem, fans work fine on a manual switch, but no kick-on by the computer.
I traced mine to the PCM, when the car is overheating, the PCM is only seeing 184 deg so it doesn't turn the fans on. You might want to hook a scanner up and check the temp the PCM is reading.
Sara Lou
I have the exact same problem, fans work fine on a manual switch, but no kick-on by the computer.
I traced mine to the PCM, when the car is overheating, the PCM is only seeing 184 deg so it doesn't turn the fans on. You might want to hook a scanner up and check the temp the PCM is reading.
Sara Lou
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From: Decatur, TN (N-W of Athens)
I use an AutoXRay scanner, and it can even data log, if I had the computer link to download the log 
It can do real time scanning of everything though. I leave it hooked up while I drive and if I get bored turn it on and check sensors 
Resembles this one, but not quite. http://www.obd-codes.com/reviews/dat...2000-large.jpg
It can do real time scanning of everything though. I leave it hooked up while I drive and if I get bored turn it on and check sensors Resembles this one, but not quite. http://www.obd-codes.com/reviews/dat...2000-large.jpg
Any of the OBD1 scanners should 'read' your computer, I used Datamaster (free for first 20 scans). If I remember right, on the '93 you can jumper pins 'A' + 'B' on the diagnostic terminal (under steering column) to get the codes, and it should also kick the fans on which will tell you if the relays, wiring, fan motors, etc are working ok.
Sara Lou
Sara Lou
my fans and everything do work. When my SES light comes on both of my fans kick on. I have a manual swith in my car for the fans with the LED. When i turn it to the left the fan kicks on, when i click it to the right both fans kick on. When i have the switch in the off position and the ses light turns on then both lights; both fans; turn on. The only time they wont turn on is when my car reaches the point at which the computer is sapposed to turn it on.
Sounds like you got the same problem as me then. Or the sensor in the water pump might be giving a false reading to the PCM. If you go to shbox.com he has a list there of what Ohms relate to what temperature that the sensor is sending.
Sara Lou
Sara Lou
Ohh, and the diference in the '93 and '94 fan setup. your low speed is one fan running, high speed 2 fans running. On my '94 low speed is both fans running at a lower speed, then both running at full speed for high setting.
Sara Lou
Sara Lou
If the fans come on with the SES light, that pretty much tests all the wiring, relays, etc., and the PCM is capable of operating the fans. Did you replace the whole PCM, or just the removable chip?.
The only thing I am doing about the PCM is to replace it, I picked up another on e-bay, just got to gef off my @## and reprogram it (came out of a 'B' body).
The first thing I would suggest for you is to check the Ohms readings at different temperatures at the sensor in the waterpump, then compare them to the list at shbox.com, if they are within acceptable range, then I would suspect the PCM.
Sara Lou
The only thing I am doing about the PCM is to replace it, I picked up another on e-bay, just got to gef off my @## and reprogram it (came out of a 'B' body).
The first thing I would suggest for you is to check the Ohms readings at different temperatures at the sensor in the waterpump, then compare them to the list at shbox.com, if they are within acceptable range, then I would suspect the PCM.
Sara Lou
