CORE GP-OIL COOLER 7E2660 - Caterpillar

Conditions Which Generate This Code:
Illustration 1 g00545923
System Schematic For CCM Data LinkNote: When a CCM is connected to a single genset, B+ is connected directly from TS1-17. When a CCM is connected to multiple gensets, the diode must be connected as shown and B+ must be wired to TS1-15. On gensets that are equipped with a CCM, the GSC+ uses the "CCM data link" to communicate with the Customer Communication Module (CCM). The CCM data link consists of two wires that connect the GSC+ to the CCM. The possible causes of a CID 0770 FMI 09 are listed below.
A short to the + battery ("B+") of either one of the two contacts, 21 or 22
A short to battery negative ("B-") of either of the two connector contacts, 21 or 22Note: The GSC+ cannot detect an open in the circuit of the CCM data link. The GSC+ treats a CID 0770 as an alarm fault. Active alarm faults are shown on the display when the "alarm codes" key is pressed and the "ECS" switch is in any position except the OFF/RESET position. Troubleshoot and repair the wiring. See Testing and Adjusting, "Schematics and Wiring Diagrams". Clear the fault from the fault log after troubleshooting is complete. Test Step 1. CHECK THE CCM FOR A SHORT TO +BATTERY
Turn the ECS to the OFF/RESET position.
Disconnect the + and - battery leads from the battery.
Measure the resistance between contacts 21 and +B.
Measure the resistance between contacts 22 and +B.Expected Result:The resistance is greater than 5000 ohms for both cases.Results:
OK - The resistance is greater than 5000 ohms for both cases.