C7 and C9 Industrial Engines Troubleshooting – Indicator Lamp – Test

The indicator lamp will turn on when a warning, a derate, or a shutdown is activated by the Electronic Control Module (ECM).

Use this procedure to troubleshoot any suspect problems with the circuit for the indicator lamp.

Illustration 1 g01122447
Schematic for the indicator lamp

The ECM provides a path to ground for the warning lamp. When the ECM connects the warning lamp to ground the warning lamp will turn on.

Table 1
Troubleshooting Test Steps	Values	Results
1. Check for Normal Operation of the Indicator LampA. Monitor the warning lamp. 1. Turn the keyswitch to the ON position. The indicator lamp should turn on for 5 seconds. If the warning lamp does not turn on, check that the bulb is not burned out or check that no breakers are tripped. After 5 seconds, the lamp should turn off. If the warning lamp does not turn off, check for an event code. Note: The lamp will only turn off only if a “Warning”, a “Derate”, or a “Shutdown” condition does not exist.	Indicator Lamp	Results: The warning lamp appears to be operating correctly at this time.STOP Results: The warning lamp is not functioning correctly. Check the bulb. Replace the bulb if the bulb is not OK. If the bulb is OK, proceed to Test Step 2.

Illustration 2 g01119456
Left side view

(1) P61 customer connector

(2) J1/P1 ECM connectors

Illustration 3 g01216602
P1 terminals that are associated with the indicator lamp

(P1-29) Indicator lamp

Illustration 4 g01216603
J61 and P61 terminals that are associated with the warning lamp

(25) Indicator lamp

Table 2
Troubleshooting Test Steps	Values	Results
2. Inspect the Electrical Connectors and the WiringA. Turn the keyswitch to the OFF position. B. Thoroughly inspect connectors (1) and (2). Inspect the connections on the indicator lamp. C. Perform a 45 N (10 lb) pull test on each of the wires that are associated with the warning lamp. D. Check the allen head screw on each ECM connector for the proper torque. E. Check the allen head screw on the customer connector for the proper torque. F. Check the harness and wiring for abrasions and for pinch points from the warning lamp to the ECM.	Electrical Connectors and Wiring	Results: The connectors and the wiring are OK. Proceed to Test Step 3.Results: There is a problem with a connector and/or the wiring. Repair: Repair the connector and/or the wiring. Replace parts, if necessary. Ensure that all of the seals are properly in place and ensure that the connectors are coupled. Verify that the problem is resolved. STOP
3. Test the Indicator Lamp Circuit at the ECM ConnectorA. Disconnect the J1/P1 connectors. B. Connect a jumper wire between terminal P1-29 and engine ground. C. Turn the keyswitch to the ON position. Observe the lamp. D. Remove the jumper wire and observe the warning lamp.	Indicator Lamp Circuit	Results: The warning lamp turned on while the jumper was connected. The warning lamp turned off when the jumper was removed. The warning lamp circuit is functioning properly. Proceed to Test Step 6.Results: The warning lamp did not turn on. There is a problem with the circuit for the warning lamp. Proceed to Test Step 4.
4. Test the Circuit at the Indicator LampA. Disconnect wire from customer connector P61-25 (indicator lamp). B. Connect a jumper wire between the lamp open terminal and engine ground. C. Turn the keyswitch to the ON position. Observe the lamp. D. Disconnect the jumper wire and observe the warning lamp.	Circuit	Results: The lamp turned on while the jumper wire was connected. The lamp turned off when the jumper wire was removed. The +Battery side of the circuit for the lamp is functioning properly. There is a problem with the return wire between the lamp and the P1 connector.Repair: Repair the wire between terminal P61-25 and terminal P1-29. Verify that the problem is resolved. STOP Results: The lamp did not turn on when the jumper wire was connected. There is a problem with the +Battery side of the circuit for the lamp. Proceed to Test Step 5.
5. Check the Voltage from the Keyswitch to the Indicator LampA. Turn the keyswitch to the OFF position. B. Remove the wire from the terminal R of the keyswitch. C. Turn the keyswitch to the ON position. D. Measure the voltage on terminal B of the keyswitch to engine ground. E. Measure the voltage on terminal R of the keyswitch to engine ground. F. Turn the keyswitch to the OFF position.	Voltage	Results: Voltage is present on terminal B and terminal R at the keyswitch.Repair: If voltage is present on terminal R, repair the wire between the keyswitch and the warning lamp. Verify that the breaker is not tripped. Return all wiring to the original configuration. Verify that the problem is resolved. STOP Results: Voltage is not present on terminal B at the keyswitch. Repair: If voltage is not present on terminal B, repair the wire between the +Battery and the keyswitch. Check the battery no-load voltage. Return all wiring to the original configuration. Verify that the problem is resolved. STOP Results: Voltage is not present on terminal R at the keyswitch. Repair: If voltage is present on terminal B of the keyswitch but not present on terminal R, replace the keyswitch. Return all wiring to the original configuration. Verify that the problem is resolved. STOP
6. Check the Operation of the ECMA. Remove terminal P1-29. B. Fabricate a jumper wire 100 mm (4 inch) long. Crimp a deutsch connector pin to both ends of the wire. C. Insert the jumper into P1-29. D. Connect the J1/P1 connectors. E. Connect one probe of a voltage test lamp to the jumper wire in P1-29. F. Connect the other probe of the voltage test lamp to +Battery. G. Turn the keyswitch to the ON position. Wait for 10 seconds. H. Turn the keyswitch to the OFF position.	ECM	Results: The test lamp turned ON for five seconds. Then, the test lamp turned OFF. The ECM is operating correctly. The problem appears to be resolved.Repair: The problem may be intermittent. If the problem is intermittent, refer to Troubleshooting, “Electrical Connectors – Inspect”. STOP Results: The test lamp did not turn on for 5 seconds. There is a problem with the ECM. Repair: Temporarily connect a test ECM. Check the operation of the warning lamp when the test ECM is installed. If the problem is resolved with the test ECM, reconnect the original ECM. If the problem returns with the original ECM, replace the original ECM. Verify that the problem is resolved. STOP

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