1990 Voyager Cooling Fan Relay Works Intermittently?

[TurboDodge]

Working on a 90 Voyager 2.5T, 5spd. Earlier in the day today while letting it warm up and looking over things, I saw the fan come on a couple times. Later while driving, the fan didn't kick on and the van started to overheat at an extended stop/idle. I returned from the drive, unplugged the CTS to see if I could get the fan to kick on, and nothing...no fan operation. So I figured the fan relay needs replaced and I have one ordered in for tomorrow. Just for kicks, I just went back down and fired it up, cold, unplugged the CTS and the fan kicked on. When the relays go bad do they usually just stop working completely or can they work intermittently like in this situation? I am just curious to hear what others have experienced with fan relay problems. I will be switching it out first thing in the morning so I will see if that fixes the prob. I am hoping does and I am not at the forefront of a wiring problem

[NAJ]

Yes they can work intermittently or you can have an intermittent electrical issue.
Verify both power sources, ground are present and if so if power is present on the output circuit.

GY...Constant Battery Power from Fuseable Link
DB...Ignition Feed from SBEC Cavity #9
DB/PK...Ground Side Control from SBEC Cavity #9
LT/GN...Output To Fan Motor

[TurboDodge]

Okay, the relay wasn't the problem. I swapped it out and the fan still doesn't kick on when the CTS is unplugged. However, I do have voltage(12-14) with CTS unplugged at the fan connector when it is disconnected from the fan motor. The voltage seemed to go away when I plugged the fan motor back in. I tried plugging in another cooling fan I had that I know to be good and it didn't operate either. Are the wire colors listed above the four wires that land at the relay? Thanks

[TurboDodge]

I confirmed that the wire colors you listed, NAJ, are in fact the four that go to the relay. I turned the ignition to the on position and checked voltage at the two power leads with the connector unplugged from the relay. I got 12 volts at both from GY...Constant Battery Power from Fuseable Link & DB...Ignition Feed from SBEC Cavity #9, to the DB/PK...Ground Side Control from SBEC Cavity #9 . I checked continuity between the the relay connector and the fan harness connector on the LT/GN...Output To Fan Motor, and it checked out. I did this same test with the engine running and the only difference was the voltage, 14. The fan won't kick on with the CTS unplugged or when the engine gets hot! I also have and aftermarket Autometer temp gauge for better accuracy than stock. Thanks for your help NAJ

[TurboDodge]

Another update. I reset the computer for the first time after installing the new fan relay. Now the fan comes on when the engine reaches 210 degrees, and it also comes on when I unplug the CTS. I guess the computer needed to be reset after installing the new relay. The fan has cycled several times since the reset and the CTS unplugging test has been successful multiple times. So I think the problem is solved! Thanks for your info NAJ!

[NAJ]