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Valentine One Radar Detector

pearly8
12-22-2009, 06:05 PM
I have a '94 Lincoln Mark VIII, on which the radiator electric fan is controlled by a 2 speed relay module.

The cooling system is good (new radiator, thermostat, fan works), but ocassionally in heavy traffic it starts to warm up.

How can you test the VCRM?

At my last service, they said no codes were found. Does that mean the relay is o.k.?

chiph
12-22-2009, 06:19 PM
Did you use the correct coolant?
While Prestone, etc. will probably be OK, you can't go wrong with using the Ford original coolant. Follow the directions if you need to dilute it -- don't use tap water.

Chip H.

DonTom
12-22-2009, 06:35 PM
I have a '94 Lincoln Mark VIII, on which the radiator electric fan is controlled by a 2 speed relay module.

The cooling system is good (new radiator, thermostat, fan works), but ocassionally in heavy traffic it starts to warm up.

How can you test the VCRM?

When I get to Reno this Thursday, I will check my Ford factory service manual and see if I can find a good place to start. I have dealt with my VCRM before in my Mustang. But intermittents are tough to find, unless you can keep it in the failure mode somehow. It might be best to just replace the VCRM.


At my last service, they said no codes were found. Does that mean the relay is o.k.?
No, there is only one code for the VCRM:

P1484 Open power to ground VCRM (variable control relay module)

This code does not show if the VCRM relay is open or intermittent. It only shows when the module itself has no power. The odds are the module itself is the problem, just as it was with my 1997 Mustang. There is a mechanical relay in the module which could be the problem. You might be able to clean the contacts on the relay, if you can get the module apart. IIRC, there are four rivets to drill out to get inside the module. It might be easier just to buy a used one on E-bay or a junk yard. The module doesn't cost all that much. The tough part is getting it out of the vehicle because of it's lousy location deep in the fender well.


-Don-

DonTom
12-22-2009, 06:44 PM
I have a '94 Lincoln Mark VIII,
The cooling system is good (new radiator, thermostat, fan works), but ocassionally in heavy traffic it starts to warm up.

I almost forgot to ask. How high does the coolant gauge get? In many vehicles, it will get up to 80% of max before the fan will even turn on. This can happen even on a cold day when in very slow traffic.

If it does not get into the red or pin, don't worry about it, unless you notice an obvious change from the way it used to behave under the same conditions.

Electric fan vehicles often have to get quite warm before the fan will turn on. And turning on the A/C (even when cold) should turn on the fan. You might want to see if turning on the A/C reduces the coolant temperature under such conditions.


-Don-