Constant Control Relay Module (ccrm)???

[SNAKEYE]

At 47K miles 'SNAKEYE' has developed an intermittent (more so than not) problem with the radiator cooling fan shutting down after a few miles of activation. I have the high speed fan override installation, which grounds the ECM to manually turn the radiator cooling fan on. It has no effect. The same override circuitry also operates an auxiliary 'pusher' fan installed infront of the A/C condenser. It's independently-powered circuit relay is grounded by the same switched ground that grounds the ECM, and the auxiliary fan works just fine, but can not provide all of the air flow required to cool down the coolant sufficiently with the A/C operating during these 90-plus-degree days. The radiator cooling fan also will not run with the A/C switched on. The A/C makes cold, but sends the temp gauge toward "H" in a hurry. When the fan does run, it, along with the 2-core radiator and the Evans high-capacity coolant pump, it can keep the gauge in around the "M" and "A" on the hottest days at any road speed.
After checking/cleaning the associated ground and power connectors, I have come to the conclusion that the constant control relay module is having a problem and needs to be replaced. Before I drop the $125 for the CCRM, has anyone had a similar problem with the same solution?

 

[COBRASVT]

Yes and yes.

You have described the problem perfectly. You are lucky in the fact that you have an aux fan grounded to the same pcm location...this pretty much seals the deal.

The CCRM actually has 3 40 amp relays built into it. The same relays you can buy from Radio Shack, but the connectors are diff so they can be mounted to the circuit board.

More than likely, one of the relays is bad since the board is solid state.

I've actually taken one a part...cut the connectors down on a relay to where they would fit and re-soldered it onto the board. This still only lasted 6 months, but it was fun doing it. That was before Ford put them in the inner fender...they used to be behind the radiator and easier to get to.

Def sounds like you've found your problem though.

NOTE: That's why your override doesn't work.....all you are doing is grounding the wire at the pcm which tells the pcm to send the signal to the CCRM (which is also a ground), but if the CCRM is out, that wont have any effect.

 

[SNAKEYE]

Thanx for the reply COBRASVT.

I took the original CCRM out of the car the other night Monday evening after inspecting and cleaning (it really wasn't dirty, but a shot of contact cleaner didn't hurt) the wire harness connection, and drilled out the rivets to get a good look inside. As you described, the relays are almost identical to the type available a RS. They are sealed better than those from RS, and soldered into the circuit board which is riveted to the metal base frame. I'd have played more with it then to see what makes it tick but didn't have time to mess with it. And to what end anyway except to have the satisfaction of examining it.
I talked with another SVT owner/enthusiast friend who confirmed that owners of S/C'd Cobra report earlier than usual failures of the CCRM due to their being more active with the heat of S/C'd cars. The other guy is an aquaintance (Ford service manger) who was non-committal.
So I dropped the $125 on the way home from work and installed it last evening. It worked in the driveway. But then it's done that when I messed with it before. The drive to work this A.M. (in about 10 minutes) will be the real test.
Thanx again!

 

[SNAKEYE]

Road test (drive to work = 30 miles) complete. Operation a success! In fact, the temp gauge (such as it is) seemed to be hanging a bit lower than usual. Perhaps I've gotten the low speed fan back that I never knew was missing!
The real test will come on the trip home when the air temp will be in the mid-80's with a dash of bumper-to-bumper thrown in for good measure.

 

[SNAKEYE]

Follow-up To Ccrm Problem

Last night I drilled out the rivets that held the circuit board to the mounting frame to see what I could see on the bottom side of the circuit board. Based on info from the schematics, I applied 12VDC to the appropriate pins of the connector to hear/feel which relay was the high speed fan relay. Sure enough, it did click, but then it did that, and not that,while in the car. I very carefully visually inspected the solder joints of all of the relays, and sure enough, where all but one looked like little volcanoes (kind of concaved sides) around the device pin, one of the pins on the high speed relay's coil looked more like a half of a ball and the tip of the pin was clearly evident with what looked like a tiny crack running around its perimeter where the half-ball of solder surrounded it. I tried jostling the pin around but could not see any evdence of mechanical looseness. Then I tried to re-solder the joint. Holy moly!, they must use some kind of high temp solder. I could bearly get it hot enough to melt the existing half-ball. Eventually it did melt and I hit it with my normal electronic-type solder. Then I threw the circuit board, frame and cover back together, taped it up for security, and stowed it away for another day when the radiator stops running, or someone else needs to do some diagnostic experimenting without dropping $125.

 

[Doug]

when my ccrm went out, my car wouldn't start and flagged a bad crank sensor on the CEL.

 

[COBRASVT]

when my ccrm went out, my car wouldn't start and flagged a bad crank sensor on the CEL.

Sounds like you had a circuit board failure...I don't think the CCRM has a relay for the crank sensor.... There are two for the fan and one for the a/c...or something like that.

 

[Doug]

it was weird. t he car would turn over and turn over and turn over but wouldn't fire. I borrowed a code scanner and ran the code and i think it was "crank position sensor" whichever sensor is right behind the coil pack on the driver side of the engine. I replaced that and it still wouldn't fire. So i called my engine builder and from what he told me, when i started to crank it, the CEL would blink - not stay on. He said that it was something else (i forget what it was) and that the general diagnostic code scanners get the codes mixed up. So he came up to throw my car on his trailer after doing some parking lot mechanics work. He thought it was a loose wire in something. He patched it but still no fix.

So, he towed it back down to his shop. Spent a couple days on it. He thought it might have been a tooth broke off the trigger wheel. he's got one of those optical scope things and he said that wasn't it. So he started tracing the wiring down. and found out it was the CCRM.