0303979 JOHNSON SPRING,Reverse lock

Illustration 1 g01331434
Schematic for the starting aid (31 pin MIC)
Illustration 2 g01331436
Schematic for the starting aid (70 pin MIC)
Illustration 3 g01625066
ECM pin location for starting aid
(43) Starting aid control
Illustration 4 g01625067
Pin locations for the starting aid on the 31 pin Machine Interface Connector (MIC).
(7) Starting aid control
Illustration 5 g01331433
Pin locations for the starting aid on the 70 pin Machine Interface Connector (MIC).
(43) Starting aid control Test Step 1. Inspect Electrical Connectors and Wiring
Thoroughly inspect the J1/P1 ECM connector and J20/P20 MIC. Inspect the terminal connections on the starting aid relay. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
Perform a 45 N (10 lb) pull test on each of the wires in the ECM connector that are associated with the starting aid. Refer to Illustration 3 and 5.
Check the ECM connector (Allen head screw) for the correct torque of 6.0 N m (55 lb in).
Check the harness and wiring for abrasion and for pinch points from the sensors to the ECM. Expected Result:All connectors, pins and sockets should be completely coupled and/or inserted and the harness and wiring should be free of corrosion, abrasion or pinch points.Results:
OK - There are no faults in the wiring and the connectors. Proceed to Test Step 2.
Not OK - There is a fault in the wiring and the connectors.Repair: Perform the following repair:Repair the connectors or wiring and/or replace the connectors or wiring. Ensure that all of the seals are properly in place and ensure that the connectors are completely coupled.Verify that the repair eliminates the fault.STOPTest Step 2. Check the Power Circuit of the Starting Aid Relay
Turn the keyswitch to the ON position.
Measure the voltage between the following contacts:
Terminal A and the battery - terminal
Terminal B and the battery - terminalExpected Result:The battery voltage should be more than 11.0 Volts DC for a 12 Volt system.The battery voltage should be more than 22.0 Volts DC for a 24 Volt system.Results:
OK - The voltage is within limits. Proceed to Test Step 3.
Not OK - The voltage is below limits between terminal A and the battery - terminal. There is a fault in the harness between the battery and the starting aid relay.Repair: Check the 30 Amp fuse. Repair the harness or replace the harness.Use the electronic service tool to clear any logged diagnostic codes and verify that the repairs have eliminated the fault.STOP
Not OK - The voltage is below limits between terminal B and the battery - terminal. There is a fault in the harness between the starting aid relay and the starting aid.Repair: Repair the harness or replace the harness.Use the electronic service tool to clear any logged diagnostic codes and verify that the repairs have eliminated the fault.STOPTest Step 3. Check the Control Circuit of the Starting Aid Relay
Turn the keyswitch to the ON position.
Measure the voltage between the following points:
Terminal C and the battery - terminal
Terminal D and the battery + terminalExpected Result:The battery voltage should be more than 11.0 Volts DC for a 12 Volt system.The battery voltage should be more than 22.0 Volts DC for a 24 Volt system.Results:
OK - The voltage is within limits. Proceed to Test Step 4.
Not OK - The voltage is below limits between terminal C and the battery - terminal. There is a fault in the harness between the battery and the starting aid relay.Repair: Check the 3 Amp fuse. Repair the harness or replace the harness.Use the electronic service tool to clear any logged diagnostic codes and verify that the repairs have eliminated the fault.STOP
Not OK - The voltage is below limits between terminal D and the battery + terminal. There is a fault in the harness between the starting aid relay and the ECM. Proceed to Test Step 4.Test Step 4. Check the Supply Voltage at the Coil for the Starting Aid Relay
Turn the keyswitch to the ON position.
Measure the voltage between terminal C and terminal D.
Turn the keyswitch to the OFF position and then turn the keyswitch to the ON position.
Check that the voltage is present with the keyswitch in the ON position.
Check that there is no voltage with the keyswitch in the OFF position. Expected Result:The battery voltage should be more than 11.0 Volts DC for a 12 Volt system.The battery voltage should be more than 22.0 Volts DC for a 24 Volt system.Results:
OK - The voltage is within limits. There is a fault in the starting aid relay.Repair: Replace the starting aid relay.Use the electronic service tool to clear any logged diagnostic codes and verify that the repairs have eliminated the fault.STOP
Not OK - There is no voltage or the voltage is out of the acceptable range. Proceed to Test Step 5.Test Step 5. Check the Output from the Power Relay for the Starting Aid
Turn the keyswitch to the ON position. Refer to Illustration 1.
Measure the voltage between the following contacts:
(B)
NEG batteryExpected Result:The battery has the proper voltage.Results:
OK - Proceed to Test Step 6.
Not OK - There is a fault in the wires between the relay and the starting aid.Repair: Repair the wires or replace the wires. Verify that the repair has eliminated the fault.STOPTest Step 6. Ground the Input to the Power Relay at the MIC
Turn the keyswitch to the OFF position.
On engines with a 31 pin MIC, disconnect P20 connector from the MIC and connect a 31 pin Breakout T.
On engines with a 70 pin MIC, disconnect P20 connector from the MIC and connect a 70 pin Breakout T.
Connect the electronic service tool to the diagnostic connector.
Turn the keyswitch to the ON position.
Use the override setting in the electronic service tool in order to engage the air inlet heater starting aid.
On engines with a 31 pin MIC, measure the voltage between P20:7 starting aid control and socket 2 battery - on the Breakout T.
On engines with a 70 pin MIC, measure the voltage between P20:43 starting aid control and socket 69 battery - on the Bre