Use this procedure to troubleshoot the electrical system if a problem is suspected with the protection override switch or if one of the event codes in Table 1 is active or easily repeated.
| Diagnostic Codes Table | ||
|---|---|---|
| Description | Conditions which Generate this Code | System Response |
| E085(1) Engine Shutdown Overridden Warning | The engine's Electronic Control Module (ECM) detects ground on the input for the protection override switch. | If an engine derate or an engine shutdown is active, the derate or the shutdown will be overridden.
The code is logged. |
| E097(1) Engine Derate Overridden Warning | ||
System Operation
If full engine power is needed, the protection override switch allows the user to override an engine derate or an engine shutdown. The wires for the protection override switch are routed from the ECM to the remote junction box. The wires are then routed to a customer supplied switch.
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| Illustration 1 | g01259011 |
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Typical schematic | |
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| Illustration 2 | g01259014 |
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P1 ECM connector (P1-64) Protection override switch | |
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| Illustration 3 | g01234146 |
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Location of ECM connectors | |
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| Illustration 4 | g01259018 |
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Connector "B" (Terminal 21) Protection override switch | |
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| Illustration 5 | g01259019 |
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Connector "G" (Terminal 26) Protection override switch (Terminal 28) −Battery | |
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| Illustration 6 | g01259021 |
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Connector "F" (Terminal 2) −Battery | |
Test Step 1. CHECK FOR AN "ACTIVE" EVENT CODE
- Turn the breaker for the ECM to the ON position.
- Connect Caterpillar Electronic Technician (ET) to the service tool connector.
- Monitor the event codes on Cat ET. Check and record any event codes.
Note: Wait at least 30 seconds in order for the event codes to become active.
- Determine if the problem is active and related to the following event codes:
- E085
- E097
Expected Result:
An E085 event code or an E097 event code is active.
Results:
- OK - An E085 event code or an E097 event code is active. Proceed to Test Step 2.
- Not OK - An event code is not active.
Repair: If the problem is intermittent, refer to Troubleshooting, "Inspecting Electrical Connectors" for the correct procedures for inspecting electrical connectors.
STOP
Test Step 2. CHECK THE POSITION OF THE PROTECTION OVERRIDE SWITCH
- Visually check the position of the protection override switch.
Expected Result:
The protection override switch is in the ON position.
Results:
- OK - The protection override switch is in the ON position.
Repair: Determine the reason that the protection override switch is in the ON position.
STOP
- Not OK - The protection override switch is in the OFF position. Proceed to Test Step 3.
Test Step 3. CHECK THE SIGNAL WIRE BETWEEN THE PROTECTION OVERRIDE SWITCH AND THE ECM
- Disconnect the wire N917-RD(Red) from the protection override switch.
- Monitor the event codes on Cat ET. Check and record any event codes.
Note: Wait at least 30 seconds in order for the event codes to become active.
- Determine if the problem is active and related to the following event codes:
- E085
- E097
Expected Result:
An E085 event code or an E097 event code is active.
Results:
- OK - An E085 event code or an E097 event code is active. The short circuit is in the wire between the protection override switch and the ECM. Proceed to Test Step 4.
- Not OK - An event code is not active.
Repair: The short circuit is most likely in the protection override switch. Replace the switch.
STOP
Test Step 4. CHECK THE SIGNAL WIRE BETWEEN CONNECTOR "G" AND THE ECM
- Disconnect the wire N917-RD(Red) from terminal 26 of connector "G".
- Monitor the event codes on Cat ET. Check and record any event codes.
Note: Wait at least 30 seconds in order for the event codes to become active.
- Determine if the problem is active and related to the following event codes:
- E085
- E097
Expected Result:
An E085 event code or an E097 event code is active.
Results:
- OK - An E085 event code or an E097 event code is active. The short circuit is in the wire between the connector "G" and the ECM. Proceed to Test Step 5.
- Not OK - An event code is not active.
Repair: The short circuit is between the protection override switch and connector "G". Replace the wire or repair the wire.
STOP
Test Step 5. CHECK THE SIGNAL WIRE BETWEEN CONNECTOR "B" AND THE ECM
- Disconnect the wire N917-RD(Red) from terminal 21 of connector "B".
- Monitor the event codes on Cat ET. Check and record any event codes.
Note: Wait at least 30 seconds in order for the event codes to become active.
- Determine if the problem is active and related to the following event codes:
- E085
- E097
Expected Result:
An E085 event code or an E097 event code is active.
Results:
- OK - An E085 event code or an E097 event code is active. The short circuit is in the wire between connector "B" and the ECM. Proceed to Test Step 6.
- Not OK - An event code is not active.
Repair: The short circuit is between connector "G" and connector "B". Replace the wire or repair the wire.
STOP
Test Step 6. CHECK THE SIGNAL AT THE ECM
- Disconnect the wire N917-RD(Red) from the P1-64 ECM connector.
- Monitor the event codes on Cat ET. Check and record any event codes.
Note: Wait at least 30 seconds in order for the event codes to become active.
- Determine if the problem is active and related to the following event codes:
- E085
- E097
Expected Result:
An E085 event code or an E097 event code is active.
Results:
- OK - An E085 event code or an E097 event code is active. The short circuit is in the ECM.
Repair: Replace the ECM. Refer to the diagnostic procedure Troubleshooting, "Replacing the ECM".
STOP
- Not OK - An event code is not active.
Repair: The short circuit is between connector "B" and the ECM. Replace the wire or repair the wire.
STOP