0324652 JOHNSON ORIFICE, 90, no. 26

If the application is equipped with two throttles, the engine will use the second throttle until the fault is repaired.If a second throttle is not installed or if the second throttle has a fault, the following conditions will occur:
The engine will default to limp home mode.
If the engine speed is higher than the speed in limp home mode, the engine will decelerate to limp home mode.
If the engine speed is lower than the speed in limp home mode, the engine speed will remain at the current speed.
The engine will remain at this speed while the diagnostic code remains active.
All inputs from the faulty throttle are ignored by the ECM until the fault is repaired.
All inputs from the repaired throttle will be ignored by the ECM until the keyswitch has been cycled.The IVS may be installed. The IVS is required for mobile applications. The IVS is part of the throttle position sensor. The IVS is CLOSED when the low idle is set.The configuration parameters for the throttle and for the IVS thresholds are programmed into the ECM. Use the electronic service tool in order to display the configuration parameters for the throttle and for the IVS.If the IVS operates outside of the programmed range, then the engine speed may not respond to changes in the throttle position.The electronic service tool may be used for the following:
If necessary, reset the IVS threshold for an existing IVS.
If necessary, view the IVS change point and reset the IVS thresholds when a new throttle assembly is installed.
Illustration 1 g03726319
Schematic diagram for the Idle Validation Switch (IVS) switch circuit
Not all connectors are shown. Refer to the Electrical Schematic for the application.
Illustration 2 g03726324
View of the pin locations on the P1 connector for the IVS circuit
(42) IVS 2
(67) IVS 1
Table 2
Troubleshooting Test Steps Values Results
1. Check for Active Diagnostic Codes
A. Establish communication between the electronic service tool and the ECM. Refer to Troubleshooting, "Electronic Service Tools"
B. Check for active or logged codes.
Diagnostic Trouble Codes
Result: There is an active or logged , 558-2 or 2970-2 diagnostic code.
Proceed to Test Step 2.
2. Check the Operation of the IVS
A. Turn the keyswitch to the OFF position.
B. Connect the electronic service tool to the diagnostic connector.
C. Turn the keyswitch to the ON position.
D. Use the electronic service tool in order to check the current "Throttle Configuration".
E. Select the "SERVICE" option from the drop-down menu of the electronic service tool.
F. Select the "Throttle Configuration" option on the electronic service tool. Select the appropriate "Throttle Configuration" summary from the menu on the left of the screen. The IVS window for the throttle will indicate "YES" if an IVS is installed.
G. Select the "Throttle status" function on the electronic service tool. Select "Status" function and then select "Throttles" function.
H. The throttle is set in the low idle position.
I. Operate the throttle slowly. The IVS status should change from CLOSED (ON) to OPEN (OFF).
Switch state
Result: The IVS state changes from CLOSED (ON) to OPEN (OFF).
Proceed to Test Step 3.
Result: The IVS does not operate
Proceed to Test Step 4.
3. Check the IVS Threshold
A. Connect the electronic service tool to the diagnostic connector.
B. Turn the keyswitch to the ON position.
C. Use the electronic service tool in order to check the current "Throttle Configuration".
D. Select the "SERVICE" option from the drop-down menu of the electronic service tool.
E. Select the "Throttle Configuration" option on the electronic service tool. Select the appropriate "Throttle Configuration" summary from the menu on the left of the screen. The IVS window for the throttle will indicate "YES" if an IVS is installed. Make a note of the "Idle Validation Min OFF Threshold" parameters that are displayed in the "Throttle Configuration" menu of the electronic service tool. Make a note of the "Idle Validation Max ON Threshold" parameters that are displayed in the "Throttle Configuration" menu of the electronic service tool.
F. To select the "Throttle status" function on the electronic service tool, select "Status" function and then select "Throttles" function.
G. The throttle is set in the low idle position.
H. Operate the throttle slowly. The IVS status should change from CLOSED (ON) to OPEN (OFF).
Switch operation
Result: The IVS switch operates within the "Idle Validation Min OFF Threshold" and the "Idle Validation Max ON Threshold" parameters.
The fault appears to be resolved.
Return the engine to service.
Result: The IVS switch cannot operate within the "Idle Validation Min OFF Threshold" and the "Idle Validation Max ON Threshold" parameters
Proceed to Test Step 10.
4. Inspect Electrical Connectors and Wiring
A. Inspect the P1/J1 ECM connector.
B. Inspect the connectors for the throttle position sensors.
C. Perform a 30 N (6.7 lb) pull test on each of the wires in the ECM connector and the connector for the throttle position sensors.
D. Check all of the wiring associated with the throttle position sensors for abrasions and pinch points.
Damaged wire or connector
Result: A damaged wire or damaged connector was not found.
Proceed to Test Step 5.
Result: A damaged wire or damaged connector was found.
Repair: Repair the damaged wire or the damaged connector.
Use the electronic service tool to clear all logged diagnostic codes. Verify that the repair eliminates the fault.
5. Check the Voltage at the IVS Switch
A. Disconnect the IVS harness connector.
B. Turn the keyswitch to the ON position.
C. Use a suitable multimeter to measure the voltage between the IVS terminal on the harness connector and a suitable ground.
D. Turn the keyswitch to the OFF position.
7.9 V to 12.2 V
Result: The voltage is within the expected range.
Proceed to Test Step 6.
Result: The voltage is not within the expected range.
Proceed to Test Step 7.
6. Check that the IVS is Grounded
A. Disconnect the IVS harness connector.
B. Turn the keyswitch to the ON position.
C. Use a suitable multimeter to measure the voltage between the IVS terminal on the harness connector the ground terminal on the harness connector.
D. Turn the keyswitch to the OFF position.
7.9 V to 12.2 V
Result: The voltage is within the expected range.
Proceed to Test Step 9.
Result: The voltage is not within the expected range. The fault is in the ground wire for the suspect IVS.
Repair: Replace the faulty wiring. Refer