Conditions Which Generate This Code:
This diagnostic code is for the limit switch (direction).
| Switch Circuits at the ECM Connector | |||||
|---|---|---|---|---|---|
| CID/ Switch |
Switch State |
ECM Connector and Contact No. |
Switch Connector Contact |
Wire No. | Status |
| CID 0623 Direction Switch |
Not Activated FORWARD and NEUTRAL | J1-23 N/O | N/O (1) | F782-OR | O (2) |
| J1-35 N/C | N/C (3) | F786-GY | G (4) | ||
| Activated (Reverse) | J1-23 N/O | N/O | F782-OR | G | |
| J1-35 N/C | N/C | F786-GY | O | ||
| ( 1 ) | N/O = Normally Open. |
| ( 2 ) | O = Open. |
| ( 3 ) | N/C = Normally Closed. |
| ( 4 ) | G = Grounded. |
This switch has two inputs to the ECM. The inputs are Normally Open and Normally Closed. During normal operation, one of the inputs is open and the other input is grounded. A problem is detected when both inputs are in the same state at the same time.
The possible causes of this diagnostic code are listed below:
- There is an open wire between the common circuit for the switch (G939-PK) and the ECM.
- There is an open or grounded wire between the Normally Open contact of the switch (F782-OR) and the ECM.
- There is an open or grounded wire between the Normally Closed contact of the switch (F786-GY) and the ECM.
- The direction switch has failed.
- The ECM has failed. This is unlikely.
System Response:
This diagnostic code causes a warning category 1 to be initiated.
Test Step 1. CHECK THE CIRCUIT FOR PROPER OPERATION.
- Turn the key start switch to the OFF position.
- Disconnect the machine harness connectors J1 and J2 from the ECM.
- At machine harness connector J1, measure the resistance from J1-15 (the return circuit) to the Normally Closed contact (F786-GY) and to the Normally Open contact (F782-OR). See table 1.
- Measure the resistance while the switch is activated. Also, measure the resistance while the switch is not activated.
Expected Result:
The measurement is the same value as the value that is listed in table 1.
Results:
- OK - The value that is measured matches the value that is listed in the table. Proceed to Test Step 3.
- NOT OK - The value that is measured does not match the value that is listed in the table. Proceed to Test Step 2.
Test Step 2. CHECK THE SWITCH CIRCUIT AT THE SWITCH.
| Switch Circuits at the Switch | |||
|---|---|---|---|
| Switch State |
Switch Contact |
Wire No. | Status |
| Not Activated (Forward/ Neutral) |
N/O (1) | F782-OR | O (2) |
| N/C (3) | F786-OR | G (4) | |
| Activated (Reverse) |
N/O | F782-GY | G |
| N/C | F786-GY | O | |
| ( 1 ) | N/O = Normally Open. |
| ( 2 ) | O = Open. |
| ( 3 ) | N/C = Normally Closed. |
| ( 4 ) | G = Grounded. |
- At the switch, disconnect the three wires from the direction switch.
- At the switch, measure the resistance between the common contact and each of the Normally Closed contact and the Normally Open contact. See table 2.
- Measure the resistance while the switch is activated. Also, measure the resistance while the switch is not activated.
Expected Result:
The measurement is the same value as the value in table 2.
Results:
- OK - The value that is measured matches the value that is listed in the table.
Repair: The machine harness has failed. The return circuit (G939-PK) could be open. The Normally Open circuit or the Normally Closed circuit could be open or shorted in the machine harness. Repair the machine harness or replace the machine harness.
STOP
- NOT OK - The value that is measured does not match the value that is listed in the table.
Repair: The switch has failed. Replace the direction switch.
STOP
Test Step 3. CHECK IF THE DIAGNOSTIC CODE IS STILL ACTIVE.
- Clean the contacts of the harness connectors.
- Reconnect all harness connectors.
- Turn the key start switch to the ON position.
- Access the VIDS. Clear all inactive codes.
- Operate the machine.
- Determine if the CID 0623 FMI 02 is present.
Expected Result:
CID 0623 FMI 02 is present.
Results:
- YES - CID 0623 FMI 02 is present.
Repair: Exit this procedure and perform the diagnostic code procedure again. If the problem persists, the ECM may have failed. Prior to replacing an ECM, always contact your dealership's Technical Communicator for possible consultation with AVSpare. This consultation may greatly reduce repair time. See the Testing and Adjusting, "Electronic Control Module (ECM) - Replace".
STOP
- NO - CID 0623 FMI 02 is not present.
Repair: The problem does not exist at this time. The initial problem was probably caused by a poor electrical connection or a short at one of the harness connectors that was disconnected and reconnected. Resume normal machine operation.
STOP