MOTOR & MTG GP-TRAVEL 3349986 - Caterpillar

Illustration 1 g03672825
VIMSTM blue light circuit
Use this procedure:
To troubleshoot a problem with the VIMSTM blue light
Or if one of the diagnostic trouble codes (DTCs) in Table 1 is active
Table 1
Communication Gateway #1 ECM (VIMSTM Main) ECM
(MID 161)
DTC(1) DTC Description System Response
823-3 Service Lamp - Voltage Above Normal Service lamp will be bright or burned out.
823-5 Service Lamp - Current Below Normal Service lamp will be dim.
823-6 Service Lamp - Current Above Normal Service lamp will be bright or burned out.
(1) DTCs are shown as CID-FMINote: Use Cat® Electronic Technician (Cat ET) to view the current state of these outputs.Possible Causes for a -3 DTC are:
Harness problem
Failed switch Possible Causes for a -5 DTC are:
Failed service lamp
Harness problem
Failed switch Possible Causes for a -6 DTC are:
Failed switch
Short to ground If excessive current flows through the circuit, a diagnostic code is generated. A short circuit to the +Battery side will also activate a DTC.Note: The -5 DTC can only be detected by the ECM when the output for the low side driver is off. The -6 DTC can only be detected by the ECM when the output for the low side ECM driver is on.
Table 2
Troubleshooting Test Steps Values Results
1. Identify Active DTC Associated With Service Lamp Circuit
DTC is present
OK - DTC is not present.
STOP
Not OK - DTC is present.
Go to Step 2.
2. Check Connections
A. Inspect the circuit harness connectors.
Connectors are:
* Clean
* Secure
* In good condition
OK - Connections are good.
Go to the process for the active DTC.
Not OK - A connection problem exists.
Repair:
A. Clean and secure connectors.
B. Verify that the problem is corrected.
STOP
Begin Process For -3 DTC Troubleshooting Here
3. Check The Machine Harness For A Short
A. Turn key start switch and disconnect switch OFF.
B. Disconnect the harness connection at the service lamp.
C. Disconnect all service lamp switch connectors.
D. Measure the resistance of the harness from the harness lamp contacts to the harness switch connectors.
Each resistance is ≥ 5K Ω(1) OK - All resistance readings are ≥ 5K Ω.
Go to Step 4.
NOT OK - One or more readings less than 5 Ω. A short exists in the circuit with the low resistance.
Repair - Repair or replace the harness.
STOP
4. Check The Switch
The key start switch and disconnect switch remain OFF.
The harness remains disconnected from the lamp and the switch.
A. Measure the resistance across the switch. Resistance is ≥ 5K Ω OK - The resistance is ≥ 5K Ω.
Perform this procedure again.
NOT OK - The resistance is < 5 Ω. The switch has failed.
Repair - Replace the switch.
STOP
Begin Process For -5 DTC Troubleshooting Here
5. Check The Service Lamp
A. Turn key start switch and disconnect switch ON.
B. Observe the status of the DTC.
DTC changes from 823-5 to 823-3. OK - DTC changes from 823-5 to 823-3.
Repair: Replace the service lamp.
After lamp replacement, confirm DTCs are not active.
STOP
NOT OK - The DTC 823-5 remains active.
Go to Step 6.
6. Check The Wiring Harness Of The Service Lamp For A Short To Ground
A. Turn the key start switch and the disconnect switch OFF.
B. Disconnect harness connection at service lamp.
C.