The sensor is used to calibrate the signal from the Speed/Timing Sensor. The sensor eliminates any mechanical errors.
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| Illustration 1 | g00696323 |
Test Step 1. Check for Connector Damage
- Disconnect the main power.
- Check the connectors and wiring for the following problems: damage, corrosion, abrasion and incorrect attachment.
Expected Result:
The connectors and wiring should be free of the following problems: damage, corrosion, abrasion and incorrect attachment.
Results:
- OK - Proceed to test step 2.
- Not OK -
Repair: Repair the connectors or wiring and/or replace the connectors and wiring.
STOP
Test Step 2. Check for a Short Circuit and/or an Open Circuit.
- Disconnect J26/P26 and J1/P1.
- Measure the resistance between P26-1 and P26-2 .
Expected Result:
The resistance should be between 110 to 200 Ohms.
Results:
- OK - Proceed to test step 3.
- Not OK - The sensor is internally shorted or open.
Repair: Replace the sensor.
STOP
Test Step 3. Check for a Short Circuit in the Wiring Harness.
- Measure the resistance from J26-1 and J26-2.
- Measure the resistance from P26-1 to engine ground.
- Measure the resistance from P26-2 to engine ground.
Expected Result:
The resistance should be greater than 20,000 Ohms for each measurement.
Results:
- OK - Proceed to test step 4.
- Not OK - The resistance is less than 20,000 Ohms indicating a short circuit.
Repair: Repair the connectors or wiring and/or replace the connectors and wiring.
STOP
Test Step 4. Check the Resistance through the Harness.
- Use a suitable piece of wire and connect P26-1 to P26-2.
- Measure the resistance from P1-18 to P1-12.
Expected Result:
The resistance should be less than 10 Ohms through the wires.
Results:
- OK - The ECM is not reading the sensor signal correctly.
Repair: Repair the wires.
STOP
- Not OK - There is an open circuit in the harness or connectors.
Repair: Repair the connectors and wiring and/or replace the connectors and wiring.
STOP
Test Step 5. Check the Signal Voltage at the Sensor Connectors.
- Reconnect all connectors.
- Decelerate the engine to low idle.
- Set a multimeter on the 20 VAC position.
- Measure the voltage between P1-18 and P1-12.
Expected Result:
The signal voltage should be greater than 6.0 VAC.
Results:
- OK - A valid signal voltage appears at the ECM connector P1. Proceed to test step 6.
- Not OK - There is a problem in the harness or the sensor.
Repair: Recheck for shorts or opens in the harness. If the problem is not resolved, adjust the air gap to approximately 0.9 mm (0.04 inch) and repeat this test.
STOP
Test Step 6. Check for Diagnostic Codes.
- Disconnect the main power.
- Connect the ET to the service tool connector.
- Connect the Battery power to the ECM. Leave the Start/Run/Stop Switches disconnected.
- Check for ACTIVE diagnostic codes.
Expected Result:
The diagnostic code 261-13 should NOT be active.
Results:
- OK - The sensor is working properly.STOP
- Not OK - A valid signal voltage appears at P1. The ECM is not reading the voltage properly.
Repair: Replace the ECM. Refer to Troubleshooting, "Replacing the ECM with a New ECM".
STOP