COVER PLATE 3747135 - Caterpillar

Illustration 3 g03780880
CEM (typical) (2) Two-pin ARD heater wire connector
Table 4
Troubleshooting Test Steps    Values    Results    
6. Check for System Voltage at the Two-Pin ARD Heater Wire Connector
A. Start the engine.
B. Establish communication between Cat ET and the ECM .
C. Perform the "ARD Nozzle Heater Circuit Test".
D. Measure the voltage between battery ground and terminal 1 on the two-pin ARD heater wire connector.
   
Equal to System Voltage    
Result: The voltage between battery ground and terminal 1 is equal to system voltage.
Proceed to Test Step 10.
Result: The voltage between battery ground and terminal 1 is not system voltage.
Proceed to Test Step 7.
   
7. Check for Output Voltage from the ARD Heater Relay
A. Start the engine.
B. Establish communication between Cat ET and the ECM .
C. Perform the "ARD Nozzle Heater Circuit Test".
D. Measure the voltage between terminal 2 on the ARD heater relay and battery ground.
Power to the ECM must be OFF before reconnecting the relay.
   
Equal to System Voltage    
Result: The voltage between terminal 2 and battery ground is equal to system voltage.
Repair: The problem is between terminal 2 on the ARD heater relay and the two pin ARD heater wire connector. Repair or replace the damaged wire. Proceed to Test Step 11.
Result: The voltage between terminal 2 and battery ground is not equal to system voltage.
Proceed to Test Step 8.
   
8. Check for System Voltage at the ARD Heater Relay
A. Start the engine.
B. Establish communication between Cat ET and the ECM . Refer to Troubleshooting, "Electronic Service Tools", if necessary.
C. Perform the "ARD Nozzle Heater Circuit Test".
D. Measure the voltage between battery ground and terminal 1 on the ARD heater relay.
Power to the ECM must be OFF before reconnecting the relay.
   
System Voltage    
Result: The voltage between terminal 1 on the ARD heater relay and battery ground is equal to system voltage.
Repair: The ARD heater relay is not operating properly. Replace the ARD heater relay. Proceed to Test Step 11.
Result: The voltage between terminal 1 on the ARD heater relay and battery ground is not equal to system voltage.
Proceed to Test Step 9.
   
9. Check for System Voltage at the ECM
A. Start the engine.
B. Establish communication between Cat ET and the ECM . Refer to Troubleshooting, "Electronic Service Tools", if necessary.
C. Perform the "ARD Nozzle Heater Circuit Test".
D. Measure the voltage between battery ground and terminal 45 on the ECM.
Power to the ECM must be OFF before reconnecting the relay.
   
System Voltage    
Result: The voltage between ECM terminal 45 and battery ground is equal to system voltage.
Repair: Repair or replace the wiring between the ECM and the ARD heater relay.
Proceed to Test Step 11.
Result: The voltage between ECM terminal 45 and battery ground is not equal to system voltage.
Repair: The ECM is not working properly, replace the ECM. Proceed to Test Step 11.
   
Illustration 4 g03780900
ARD combustion head (3) Port for the heated nozzle
Illustration 5 g03780902
(4) Connector for the heated nozzle (5) Measurement location on the wire
Table 5
Troubleshooting Test Steps    Values    Results