irish4u

A/C was not working well and Engine temps high. Very little air flow from the fan so I changed the fan clutch with a Dorman brand clutch. It still does not work. My question is regarding the signal to engage the clutch. It has 5 wires and the pins are: 1= fan clutch control, 2= sensor ground, 3= fan speed sensor, 5= 5 volt supply, 6= 12 volt fused ignition switch output (run).
So based on this and reading the service manual I am wondering if I connect pin 1 to ground, and pin 6 to positive 12 volts will this engage the clutch so I can verify it works. Anyone have an idea?

ramman

I don't have prints here ,but grounding pin 1 will request fan on 100%,it's not like a solenoid action,it requires a few seconds to ramp up and down in speed.

AH64ID

If the fan rpms are lower than the threashold it will set a code, a soft code thou so you don't get a CEL. Hook up to a scanner and see if you have an issue.

BigIron70

TEST PROCEDURE
DIESEL
NOISE
NOTE: It is normal for fan noise to be louder (roaring) when:

Fan duty cycle high. This may occur when ambient (outside air temperature) is very high.
Engine loads and temperatures are high such as when towing a trailer.
Operating conditions where transmission temperatures may be high
Cool silicone fluid within the fan drive unit is being redistributed back to its normal disengaged (warm) position. This can occur during the first 15 seconds to one minute after engine start-up on a cold engine.
LEAKS
Viscous fan drive operation is not affected by small oil stains near the drive bearing. If leakage appears excessive, replace the fan drive unit.

ELECTRONICALLY CONTROLLED VISCOUS DRIVE - DIESEL




If the fan assembly does not free-wheel and a metallic grinding sound exists, replace the electronically controlled fan drive (Refer to 7 - COOLING/ENGINE/RADIATOR FAN - REMOVAL).

NOTE: The following test may take up to 15 minutes to perform.

The engine should be at normal operating temperature.

Set the parking brake and verify the transmission is in park or neutral.
Set air conditioner (if equipped) and blower fan to OFF.
Start and allow engine to reach normal operating temperatures.
Stop engine, connect the scan tool and select appropriate model year and engine option.
Check for and correct existing DTC's
Using Tool 6801, backprobe pin 1 of the electronically controlled viscous fan drive connector, with the harness connected located at the lower fan shroud to battery ground.
NOTE: The fan drive control coil is energized to 12 volts at this time.

WARNING: A spark may occur when connecting pin to ground. Be sure that no combustible material is in the area.

Using the scan tool, verify that DTC 0480 set. If it is not set, verify that a good ground is available.
Start the engine.
Actuate engine speed to 2000 RPM..
Go to the SENSOR screen and observe the fan speed.
Run the engine at 2000 RPM until the fan speed increases to 1850 RPM or more for 30 seconds.
NOTE: Fan RPM may ramp up slowly.

NOTE: It maybe take 15 minutes before fan speed increases.

The fan speed should be in accordance to the table below.
If fan speed does not increase, make sure that the jumper wire has a good connection. If so replace the electronically control viscous fan drive.
If the fan speed does increase and there is still a concern, refer to the appropriate Engine Electrical Diagnosis Section to diagnosis the electronically controlled viscous fan drive control circuit.
ELECTRONICALLY CONTROLLED VISCOUS FAN DRIVE SPEEDS
ENGINE RPM FAN RPM (Min)
1000 950
1500 1420
2000 1850
2500 2230

irish4u

Thanks for your reply's. Here is what I found. Code with old fan clutch was P0480. Code with new fan clutch was P0483. I connected pins 1 and 6 to the battery and the new fan clutch works fine. I tested through the back of the fan clutch plug for correct readings. The 12v supply was not making it through the connection. After messing with it for a while I decided to cut off the original plug on the bad fan clutch and splice it to the new one. I soldered and heat shrunk it until it was sealed and looked like factory. Everything checks out on the meter and it works great now. The aftermarket plug on the Dorman unit looked ok, but was not the best fit. Thanks.

CoastalDav

I found my plug loose when I first got my truck and the fan not working very well. Put a small tie wrap around it. Been good ever since.

Dave

C Schomer

I always replace the t-stat first cuz they are so short-lived. The stats in the 2nd gens didn't live long cuz they cycled so much and these aren't any better. $28 is cheap insurance. Mine was already bad before 60k miles. For proof, put the old and new stat in water and heat them on a stove. The new one opened half and again as far as my old stat. The fan can't know it's supposed to run faster if the heat isn't getting out of the engine and into the radiator. Craig

irish4u

Ok, so my new fan clutch is working, but not performing well. The ECM doesn`t seem to be able to control it very well. Kinda like its not very variable. Engine temp goes up to 218 degrees often before the fan comes up to speed then it drops quickly to 190. I changed the thermostat but it is still the same. No codes but not right either. Maybe the Dorman clutch is not very good. Can the ECM re-learn how to control the clutch?

Spooler

This sounds like the symptoms of an air pocket. In the morning pop the radiator cap off. If your radiator is not full to the top, then you have an air pocket.

bullrambler

I had this code come up today and will have to check it out to rectify the problem. Pictures would help.

irish4u

Just a follow up. I did replace the Dorman brand clutch I put in with a Mopar one. Works perfect now. Some parts gotta be OEM I guess. I also installed an electric fan in front of the condenser and now my A/C works great even when stopped in traffic on hot days.

irish4u

Now the Mopar clutch is not operating correctly. The clutch stays fully engaged which causes the belt to squeal at 2k rpms. I disconnected the plug to the clutch and the clutch releases. I don't know if it's a clutch problem or the control signal.