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Ok, so here's a question that may or not be lame. To activate the fans on the computer driven 95 camaro engine, the sensor in the water pump needs to read 226 degrees. Can you activate it by shorting (connecting) the wires running to the sensor? I'm wanting to test it and getting the sensor to 226 is not feasable. Any ideas as to how to test it? Thanks!
No. That sensor is a thermistor, not a switch. Are you testing the sensor,or the ECM? Is the engine running in a car or are you testing it out before you pull it?
Using a "jumper" on the CTS/ECT connector is thought to indicate to the ECM/PCM that the temp is 130°C (286°F) OR greater so if you felt the cooling fans/relays/wiring etc were correct you would expect fan operation I'd think.
Do you have any sort of scanner or PC application for use as a scanner? You need to confirm in some fashion that it's the value the PCM sees.
For an application similar to yours it might seem that maybe switched operation of the fans might be more practical. You're using what for a radiator and what for cooling fans?
radiator and cooling fans out of a camaro as well. no scanner. what is the CTS connector? I'm wanting to make sure the fans are wired correctly so I can test them but i cant get the engine warm enough. With the goofy ground signal from the ECM i want to test my relay wiring. If it were mine, id put a switch in, but the guy im doing it for wants it automatic.
ok thats what i was thinking. short which one to ground? both wires coming out of the sensor are black and they were cut before I got the engine, so I'm not sure which wires from the harness should go to which wire on the CTS plug (does it matter?)
ok thats what i was thinking. short which one to ground? both wires coming out of the sensor are black and they were cut before I got the engine, so I'm not sure which wires from the harness should go to which wire on the CTS plug (does it matter?)
ok. i jumpered either of them to ground and nothing happened with the key on or off. I have the relays wired like this (found at lt1swap.com). One relay per fan. Is this correct? It would appear it is not, but please point me in the right direciton. thanks
Last edited by matthewsorrells; Nov 30, 2016 at 04:12 PM.
ok. i jumpered either of them to ground and nothing happened with the key on or off. I have the relays wired like this (found at lt1swap.com). One relay per fan. Is this correct? It would appear it is not, but please point me in the right direciton. thanks
You "jumper" the terminals of the connector with a single length of wire - NEITHER to ground - you want the ECM to do the grounding to activate the circuit for fans. Your fan wiring schematic I'm not familiar with for the F-body. I believe you get your hands on some sort of software to use with a PC or a scanner to confirm PCM communication with all of the related sensors to make the car and accessories RUN.
I believe for your install you've attempted to duplicate the GM/OE wiring so maybe just try to duplicate the way the original was. I believe it would have been like one of these in this link. Which? If you dismantled the donor car maybe you know. If the donor is still available maybe you look at the car. Is there a GM label on either fan motor that might ID the motor?
dang man. now I'm really confused. I THINK you suggested i - in effect - just touch the wires together.
The donor car is an hour away and likely no longer in existence. It was a 95 firebird ws1.
I'm about to just get a kit or a 200 degree switch to replace the temp sensor with and just rewire it. Didnt think i was reinventing the light bulb. I think the original had 3 relays, but for the life of me I cant understand why it wouldnt be done with 2. From what I'm reading many people do it with 2 but i cant seem to make it work.
Dang, man! You asked for help and WVZR-1 is trying to help you. Listen to him. Don't try to re-invent stuff. It would help if you'd read his posts more carefully!
A 100 ohm resistor inserted into the sensor plug will trick the engine computer to think its about 240* and will bring on the fans to high. 3 relays allow the cooling system to have several capacity steps instead of just on-off. It keeps the engine temperature swings smaller.
Stop the madness. All you have to do is jumper pins 5 and 6 of the DLC (datalink connector). With the ignition on and engine not running, that will turn on both fans and several other devices.
Stop the madness. All you have to do is jumper pins 5 and 6 of the DLC (datalink connector). With the ignition on and engine not running, that will turn on both fans and several other devices.
Providing the OP has used the later 16 pin DLC & has the diagnostic port (FSE) in his wiring scheme and has corresponding cooling fans pinned appropriately to the PCM. Much would depend upon the way the OP has done the wiring.
OP - did you use the DLC from the Camaro and have you got D20 wired to PIN 6 of the DLC?
WVZR-1, I meant no disrespect. I do appreciate all the help, and I guess I came across wrong. Sorry about that. It does have the factory harness from a 95 firebird. There is no datalink connector but just the harness. I'm sorry I dont really know the numbers of the wires, I figured it out based on the wiring harness plug numbers like c100, c105, and such. I got pins from radio shack and plugged those into the original harness so I wouldnt destroy the harness. If it was my vehicle, I would have cut the harness open and chased wires, but the feller I'm doing it for wanted to retain the harness if he ever wanted to sell the engine I guess.
I ended up just buying a $10 fan switch that comes on at 212 degrees and I had it wired in 10 minutes to working condition. Sometimes the simplest solutions are the best. Thanks for your help!
fan activation
