The temperature light and the engine temperature goes up high. I
replaced the Thermostat thinking it was that but it still gets hot. I took notice
that the Electric Radiator Fans do not kick on. I took notice that when the
van is being driven that the temperature stays at a fairly stable level, but
when the van is stopped at a light,traffic ,etc. the temperature wants to
go up. Is those 2 fans capable of cooling the Radiator fluid ? Would anybody
have a small drawing of the Fan Circuit? What Temperature are those fans
set to start? Also I could not find the relay labeled fan, I did see 1 labeled
blower ,but I believe that would be for the interior blower for the heat/
defrost/ AC.
Thanks in advance
RickMN
06-29-2007, 01:01 PM
The fan relay is located on the front of the left frame rail. It gets power from fuse #4 40A. The PCM sends a signal to the relay to turn the fans on low speed when engine temp is 220°. It commands high speed at 230°. Check your engine coolant temperature sensor and the wiring at the relay. Unplug the connector at the relay. Connect a jumper wire between the gray wire and the dark green wire. If the fans operate, you know the fans are good and power to the relay is good. Next, disconnect the wiring harness at the PCM. Check resistance between terminal #73 (light green/dark blue) and ground. If you see 5 or fewer ohms, you've got a short to ground somewhere. Then check resistance between relay terminal #3 (light green/dark blue) and PCM terminal 73. If you get more than 5 ohms, you have an open between those two components. If resistance is less than 5 ohms, it's a PCM problem.
If those tests come out ok, then check the engine coolant temp sensor.
XDGT03
06-29-2007, 03:19 PM
^^^ Follow that advice. It is likely the relay which is about $55. It is a cheap part to fix your overheating problem but an expensive one if that isn't the problem. So do as rick said. If you have to replace the relay I recommend disconnecting the battery for at least 15 minutes. I think this causes the PCM to reset. I replaced my relay and my fans still didn't work. I think disconnecting the battery is what got them working.
RSmith
06-30-2007, 10:59 AM
I still cannot find the Fan Relay. Is it on the main fuse /relay board. What
do you mean by the "Front of the Left Frame Rail ". I found the fuse.
Thanks,
XDGT03
07-01-2007, 06:43 PM
It is under the air cleaner box, on the support for the radiators. It is screwed to face of the rail that is in the engine compartment. You may need to remove the air cleaner assembly. Mine is permanently removed and replaced with a short ram intake with cone filter.
Jack up the front end and support with jack stands. Get underneath the driver's side from the front and look up. It is right there. Get a flashlight or drop light and you will see it. It has a 4 wire harness running to it.
Make sure the surface that it mounts to is clean. I believe the body of the relay grounds to the frame. The back of the relay is metal. If it didn't ground then I don't know why it would be metal. Use dielectric grease.
