Challenger 35, Challenger 45 and Challenger 55 Agricultural Tractors Electronic Systems Caterpillar

Illustration 1	g00562250
(1) Chassis Control Module. (2) Speed Sensor (Transmission). (3) Speed Sensor (Engine).

This fault code indicates the engine RPM sensor has a higher than normal voltage and may be due to an open circuit, a short to positive voltage, or an open sensor.

1. Inspect engine RPM sensor connector (C160) to determine whether the connector is disconnected or damaged.

   Expected Result: There is a damaged harness. The sensor is corroded. A connector is separated.

   • YES, reconnect or repair as appropriate and recheck fault codes. If fault code is not active, repair is complete.

   • NO, go to Step 2.

2. Disconnect engine RPM sensor and measure the resistance across terminals A and B. The resistance should be 2550 ohms.

   Expected Result: There is an open circuit.

   • YES, replace engine RPM sensor. Check fault code and if no longer active the repair is complete.

   • NO, go to Step 3.

3. If the transmission speed sensor is functioning properly, exchange the transmission speed and engine RPM sensors. Check fault codes.

   Expected Result: The fault code is not active.

   • YES, install new engine RPM sensor. Check fault code and if no longer active the repair is complete.

   • NO, go to Step 4.

4. Disconnect Chassis Control Module connector C002. Check for open circuit between C160-1 and C002-4, then C160-2 and C002-8.

   Expected Result: There is an open circuit.

   • YES, locate and repair open circuit in Rear Main harness. Check fault code and if no longer active the repair is complete.

   • NO, go to Step 5.

5. Check for short circuit from the positive terminal of the battery (+12 volts) to terminal C160-1.

   Expected Result: There is a short circuit.

   • YES, locate and repair short circuit in Rear Main harness. Check fault code and if no longer active the repair is complete.

   • NO, go to Step 6.

6. Download latest control module software into all control modules.

   Expected Result: The fault code is active.

   • YES, go to Step 7.

   • NO, repair is complete. Calibrate transmission and three-point hitch.

7. Replace the Chassis Control Module (CCM).

   Expected Result: The fault code is active.

   • YES, install the original CCM and repeat this troubleshooting procedure.

   • NO, go to Step 8.

8. Install the original CCM.

   Expected Result: The fault code is active.

   • YES, original CCM was faulty. Replace original CCM with new CCM. If fault code is not active, repair is complete. Download latest control module software into all modules. Calibrate transmission and three-point hitch.

   • NO, this fault code may have been caused by faulty connectors. Keep the original on the tractor. Clean all terminals on the CCM and reconnect. If fault code is not active, repair is complete. Download latest control module software into all modules. Calibrate transmission and three-point hitch.