From Mechanical Database
|If any modifications on the CCRM are to be performed, acquiring a spare one from an auto salvage yard or other sources may be a good idea, since the vehicle will not work if the CCRM is damaged.|
The following how-to is on how to repair the CCRM (constant control relay module) on 97-03 2.0 Ford Escorts and ZX2s. The most common problem of a bad CCRM is that the a/c stops working. Causing the radiator fan to work, but not the clutch on the A/C compressor itself. The solution is to either fix the old CCRM, buy a new one, or bypass the relay.
A part number of the old CCRM is required to purchase a new one. In the following photos, they may seem different, but the last two letters "BC" are what determine the compatibility. A new CCRM will run about $200-250 from Ford. Matching the part number and checking compatibility is important as there are several different designs. Most of the wiring changes occur on the radiator fan relay.
- Disconnect the negative battery terminal.
- Remove the air filter enclosure. It is secured by 3 12mm bolts.
- Remove the mount that holds the CCRM.
- Unplug the CCRM, and then plug a new one in.
- Reinstall the air box and reconnect the battery.
Repairing the relay is a much more affordable approach that is fairly simple. The most difficult task is drilling out the rivets for the unit. Upon opening the unit, 5 relays are revealed.
The smallest of the 5 relays is the WAC relay (omron G8SN-UA-007116) which controls clutch operation.
The two main causes of failure is either a faulty WAC relay or a bad solder joint.
Solder joint repairOften times it's a cold solder joint, which means that the lead and solder are not making contact. The following picture reveals the location of the bad solder joint.
A soldering iron will be required to resolder it. Any cheap 30-40 watt soldering iron will suffice. Before soldering, removal of the anti-moisture gel around the area is required. Once it is removed, the joint should be heated, and new solder applied. Inspect the joint and make sure the connection is solid. Using excessive solder to make the connection may be required, due to the anti-moisture gel.
Replacing the relay is a little more complicated. It requires removing the original relay and replacing it with an aftermarket one. A replacement can be purchased in RadioShack, part number 275-005. It is the same saize and has the exact same pin pattern. However the relay is rated 7-9VDC instead of 12VDC, while it is suitable for this repair, it's overall lifespan may be slightly shorter.
After repairing the cCRM, now that the rivets are gone, two small machine screws will be required with nuts to close it. These are available at any hardware store.