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I just put the engine back in my '96 and the fan does not function. I bought the car with a spun rod bearing, so I don't know if it worked before. The 60A fuse is good and power to the dist. block., but no power to the fan. I need a wiring diagram to diagnose.

Does anyone have knowledge of the cooling fan operating strategy (i.e. conditions fan is operated under) and what the source of the conditions are (i.e. sensors used)?
 

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I just put the engine back in my '96 and the fan does not function. I bought the car with a spun rod bearing, so I don't know if it worked before. The 60A fuse is good and power to the dist. block., but no power to the fan. I need a wiring diagram to diagnose.

Does anyone have knowledge of the cooling fan operating strategy (i.e. conditions fan is operated under) and what the source of the conditions are (i.e. sensors used)?
I have a tune from the 97 in my car, but the 96 tune is probably identical. these parameters are from the stock 97 tune:

The stock low speed fan comes on when the ECT hits 208 degrees. The low speed fan turns off when the ECT drops down to 200 degrees. The low speed fan will turn off when you hit 45 MPH. It will turn back on when you drop down to 40 MPH.

There is a parameter to invert the low speed fan control output in case you are using non stock fan control relays.

There is a switch that can enable or disable a high speed fan mode in case you have only one fan speed. Stock is enabled.

The high speed fan comes on at ECT at 228 degrees. It turns off as your ECT drops below 224 degrees.

There are some other parameters in the tune that can also be adjusted. The intent is to be able to turn on the fan at higher loads. The parameters are: High Speed Fan High Load Temp to Turn On (stock value = 228 degrees), High Speed Fan High Load Vehicle Speed to Turn On (Stock = 40 MPH), High Speed Fan High Load RPM to Turn On (Stock = 1808) and High Speed Fan High Load to Turn On (Stock = 0.600).

I'll look for the wiring diagram next.
 

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There is a BK/O wire that comes from the fusebox to a splice (S102) where it splits into two wires that go to CCRM pins 3 and 4. Inside the CCRM, those two pins power two relays, called EDF Relay and HEDF Relay.

The EDF relay is controled by a CCRM component labled "Solid State" which has a DB control wire running from pin 45 of PCM connector C294 to pin 14 of the CCRM. The output of the EDF relay goes to two R/O wires at CCRM pins 1 & 2. They meet at a splice (S122) and go to the fan.

The HEDF relay is controlled by a LG/P control wire coming from pin 46 of PCM connector C294 to pin 17 of the CCRM. The output of the HEDF relay goes to two O/LB wires at CCRM pins 6 & 7. They meet at splice S140 and go to another terminal of the fan. From the fan, there is a BK ground wire running to ground G103.

Hope this helps.
 

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...and where is the physical location of the relays?
They are a part of the CCRM (Constant Control Relay Module). You have to replace the entire CCRM if it fails, as I did when my fuel pump relay failed a year or so ago.

It is up under the passenger side front fender. You need to partially remove the fender liner to get to it.
 
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