Well okay I just got a new motor put into the car and the fan problem is really making me not happy. I have did searches and looked at the tech aids and checked over the wiring diagrams. Here is the scoop on the situation. I want to wire in my aftermarket fans into my stock fan wiring. I cut the plug off of one of the fan wires(black/brown). My fans have a simple power and ground coming off them. Here is what I have checked.

Put car in Service Mode
Checked Relays (3 Relay System)
Checked fuses.
Checked power at all of the fan connections NOTHING! No trace of power. In the wiring schematic it looks as if there is a internal ground in the stock fans so I grounded the black wire, used the brown as power and grounded the fans out seperate.. Still nothing. I just can't seem to trace down the weak link. With the car in service mode all the fans should have power going into the wiring.

What to check next?

 

If you have A/C, check for power at PCM B21 and A11 with the A/C on. A11 will energize the fans with the 3 relay setup. Also, you can ground PCM C25 (CTS) and that should energize PCM A10. Let me know if this doesn't work.

Also, are you sure the fans are working. Have you hooked up a direct power source to the fans?

 

Pull relay 1 and see if you have 12v on D1 in the socket. Also, have you verified that the relays are actually operating when you put it into field service mode?

 

When I put a relay in there in service mode I hear them click. But I haven't actually test them because I am not sure how to exactly do it. I have tired everything I knew how to do. Im willing to try anything else. Just tell me how to do it and Ill try it. My last resort is putting in a external fan control

 

When the coil side of the relay is powered up with 12 volts and ground, the contacts will change state. By that I mean there is a Common, a Normally Open and a Normally Closed contact. That means with no power applied to the coil side of the relay, the common connection (D1) is connected to the NC contact (D3). So those 2 points are connected together. The other contact point, (D4) is not connected to anything. Thus it is labeled NO.

When the coil is powered up with 12 volts and ground, the Normally Closed contact(D3) is now open. That is, it is no longer connected to the Common contact. Now with power applied to the coil, the C contact(D1) is now connected to the NO contact (D4).

Now that schools is over, what you need to do is see if power is at the appropriate contact such as D1 all the time. Then see if the relay is powered up, that voltage should now be at D4. If you don't see voltage at D4, see if the relay is operating by artificially powering up the relay and confirm the relay now has continuity (0 ohms) from C to NO.

 

Well I checked it over and over. Tired to hook up the stock fans with the car in diagnostic mode. Still nothing swapped relays out and still nothing. This thing has me stumped.

 

The schematic should give you all the info you need to know (if you can read/understand it). The PCM supplies a ground to the relay to operate the relay coil. Operation of the relay coil connects 12v to the fans, so they will run. That's a simplified version, but all you have to do is follow the circuit paths to see where they go.