CAP-BEARING 1606303 - Caterpillar

The relay module contains the fuses and terminals 16 to 27. The relay module is part of the back of the Status Control Module (SCM).
Disconnect the wire from terminal strip 1 in the remote control panel. Check in order to be sure that there is no voltage on the +Battery terminal of the SCM. Some of the harness may need to be removed for easy accessibility. Moisture can be introduced into the SCM when the relay housing is removed. Remove the relay housing in a dry environment. Open this housing in an air conditioned area if relative humidity exceeds 60 percent.
Illustration 1 g00326426
Location of relay housing (1) Relay housing. (2) Screws.
Remove screws (2) and washers that hold relay housing (1) to the main housing. To open the housing, install the forcing screws in the two threaded holes. The threaded holes are on the ends of the housing flange and in the same bolt pattern as screws (2). Tighten the forcing screws. If necessary, insert the thin blade of a knife between the relay housing (1) and the main housing. Gently insert the blade into the gap by lightly tapping the blade in order to break loose the seal.
Illustration 2 g00326427
Relay locations (3) "K7" Fuel Control Relay (FCR) (3E-7573). (4) "K6" Magneto Shutoff Relay (MSR) (5) "K1" 2301A Ramp (2301A). (6) "K5" Run Relay (RR). (7) "K2" Fault Shutdown Relay (ENFR). (8) "K4" Starting Motor Relay (SMR). (9) "K3" Crank Termination Relay (CTR).
Open the housing and locate the relay or the relays that need to be changed. The relays are tagged "K1" through "K7" on the PC board.
Remove the relay clip. Pull out the relay.
Do the "Relay Performance Test". Check continuity with the ohmmeter by using the following method:
With no power on terminals 7 and 8, there should be 1 Ohm or less between terminals 1 and 5. There should also be 1 Ohm or less between terminals 2 and 6. Coil resistance between terminals 7 and 8 should be 140 to 180 Ohms.
Apply 12 volts to terminals 7 and 8. There should be 1 Ohm or less between terminals 3 and 5. There should be 1 Ohm or less between terminals 4 and 6. There should be 100k Ohm or more resistance between any other pairs of terminals.
Replace the relay if the relay fails this test. Reinstall the clip.
Check the connector that is going from the main housing of the SCM to the relay PC board in order to ensure that the connector is still inserted properly.
If replacing the relay does not fix the problem or if the relay is not faulty, then replace the entire relay module.
Clean the sealing surfaces. Apply 169-5464 Quick Cure Primer to the sealing surfaces of both of the housings.
Apply a continuous bead of 6V-6640 RTV Silicone Sealant to the main housing sealing surface.
Install relay housing (1) on the main housing of the SCM. Fasten the housing with the original washers and screws (2) .
Reconnect the wires that were removed.