37920-95500 Suzuki IGNITION TIMING SWITCH

Illustration 1 g01220721
Schematic
Illustration 2 g01026818
P1 ECM connector
(P1-4) +8 V digital supply
(P1-5) Digital return
(P1-66) Decelerator position
Illustration 3 g01094844
Sensor connector
Test Step 1. Inspect Electrical Connectors and Wiring
Remove the electrical power from the ECM.
Thoroughly inspect the J1/P1 connector for the Electronic Control Module (ECM), J61/P61 machine connector, and the connector J405/P405 for the decelerator position sensor. Refer to the diagnostic functional test Troubleshooting, "Electrical Connectors - Inspect".
Perform a 45 N (10 lb) pull test on each of the wires in the ECM connector and the sensor connectors that are associated with the active diagnostic code.
Check the ECM connector (allen head screw) for the proper torque. Refer to the diagnostic functional test Troubleshooting, "Electrical Connectors - Inspect".
Check the harness and wiring for abrasions and for pinch points from the sensors back to the ECM. Expected Result:All connectors, pins, and sockets are completely inserted and coupled. The harness and wiring are free of corrosion, of abrasion, and of pinch points.Results:
OK - The harness and wiring are OK. Proceed to Test Step 2.
Not OK - There is a problem in the connectors and/or wiring.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 problem.STOPTest Step 2. Inspect the Decelerator Pedal Assembly
Inspect the decelerator pedal assembly for components that are loose, bent, missing, or worn.
Slowly depress the pedal and release the pedal. Expected Result:The decelerator pedal assembly operates smoothly without excessive drag. The pedal returns to the fully released position without assistance in less than one second.Results:
OK - The decelerator pedal assembly functions properly. Proceed to Test Step 3.
Not OK - There is a mechanical problem with the decelerator pedal assembly.Repair: Repair the decelerator pedal assembly, as required.STOPTest Step 3. Check the Status for "Decelerator Position"
Connect the Caterpillar Electronic Technician (ET) to the service tool connector.
Restore the electrical power to the ECM.
Observe the status for "Decelerator Position" on Cat ET while you operate the decelerator pedal. Expected Result:The status is approximately 0 percent when the decelerator pedal is released. The status progressively increases to 100 percent when the decelerator pedal is fully depressed.Note: This range can change depending on the adjustment of the decelerator pedal assembly.Results:
OK - The decelerator position sensor is working properly.Repair: Refer to the diagnostic functional test Troubleshooting, "Electrical Connectors - Inspect" if the problem is intermittent.STOP
Not OK - The status is not correct on Cat ET. Proceed to Test Step 4.Test Step 4. Check the Supply Voltage at the Sensor
Remove the electrical power from the ECM.
Disconnect the J405/P405 connector for the decelerator position sensor.
Restore the electrical power to the ECM.
Measure the voltage between terminal A and terminal B at the sensor connector.
Remove the electrical power from the ECM. Expected Result:The voltage is 8.0 0.5 VDC.Results:
OK - The voltage is 8.0 0.5 VDC. The voltage is correct. Proceed to Test Step 5.
Not OK - The voltage is not 8.0 0.5 VDC. The voltage is incorrect.Repair: Troubleshoot the digital sensor supply. Refer to the diagnostic functional test Troubleshooting, "Digital Sensor Supply Circuit - Test".STOPTest Step 5. Check the Isolated Signal Frequency and the Duty Cycle at the Sensor
Install a 7X-6370 Adapter Cable As (3-Pin Breakout) at the connector J405/P405 for the decelerator position sensor.
Remove the wire from the harness side of the connector P405-C (Signal).
Restore the electrical power to the ECM.
Measure the frequency and the duty cycle between terminal B (Digital Return) and terminal C (Signal) at the breakout while you operate the decelerator pedal.
Remove the electrical power from the ECM.
Reinstall the wire in P405-C (Signal). Expected Result:The frequency is between 150 and 1000 Hz. The duty cycle is approximately 57 percent when the pedal is released. The duty cycle is approximately 32 percent when the pedal is fully depressed.Results:
OK - The sensor is producing a valid signal. Proceed to Test Step 6.
Not OK - The sensor is not producing a valid signal.Repair: Replace the decelerator position sensor.Verify that the repair eliminates the problem.STOPTest Step 6. Check the Signal Frequency and the Duty Cycle at the ECM
Install a 208-0059 Adapter Cable As (Seventy-Pin Breakout) at ECM connector J1/P1.
Restore the electrical power to the ECM.
Measure the frequency and the duty cycle between P1-66 Decelerator position and P1-5 Digital return at the breakout while you operate the decelerator.
Remove the electrical power from the ECM. Expected Result:The frequency is between 150 and 1000 Hz. The duty cycle is approximately 57 percent when the pedal is released. The duty cycle is approximately 32 percent when the pedal is fully depressed.Results:
OK - A valid sensor signal is reaching the ECM. Proceed to Test Step 7.
Not OK - A valid sensor signal is not reaching the ECM.Repair: Repair the signal wire.Verify that the repair eliminates the problem.STOPTest Step 7. Check the Status for "Decelerator Position"
Restore the electrical power to the ECM.
Observe the status for "Decelerator Position" on Cat ET while you operate the decelerator pedal. Expected Result:The status reads approximately 0 percent when the decelerator pedal is released. The status progressively increases to 100 percent when the decelerator pedal is fully depressed.Note: This range can change depending on the adjustment of the decelerator pedal assembly.Results:
OK - The decelerator position sensor is working properly.Repair: Refer to the diagnostic functional test Troubleshooting, "Electrical Connectors - Inspect" if the problem is intermittent.STOP
Not OK - A valid signal appears at the ECM, but the ECM is not reading the signal properly.Repair: Replace the ECM. Refer to electronic troubleshooting Troubleshooting, "Replacing the ECM".STOP