Circuit/System Testing
WARNING: This page is about a different car, the 2007 GMC Sierra and 2007 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.
- Ignition OFF, disconnect the harness connector at the SAS.
- Test for less than 1.0 ohm of resistance between the low reference circuit terminal 2 and ground.
- If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the EBCM.
- Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal 1 and ground.
- If less than the specified range, test the 5-volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the EBCM.
- If greater than the specified range, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the EBCM.
- Test for 4.8-5.2 volts between the 5-volt reference circuit terminal 1 and the signal circuit terminal 6.
- If less than the specified range, test the signal circuit for an open/high resistance. If the circuit tests normal, replace the EBCM.
- If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the EBCM.
- Ignition OFF, reconnect the SAS.
- Disconnect the EBCM harness connector.
- Test for infinite resistance between the signal circuit pin 4 and ground.
- If less than the specified range, test the signal circuit for a short to ground.
- Disconnect the SAS.
- Reconnect the EBCM harness connector.
- Ignition ON, test voltage of phase A, phase B, and phase C. Verify that the reading is battery positive voltage for each of the three phases.
- If not the specified value, test the phase A, phase B, and phase C circuits for a short to ground or an open/high resistance. If the circuit tests normal, replace the EBCM.
- Ignition OFF, reconnect the SAS. Turn the ignition ON. Using the scan tool, rotate the steering wheel and observe the SAS. Verify the sensor sweeps through the entire range while monitoring the steering wheel as it rotates in degrees from the input signals between circuit phase A and the signal circuit phase B. The rotation in degrees should vary between phase a and phase B without any spikes or dropouts.
- If not within the specified range or is erratic, replace the steering angle sensor.
- If the sensor test normal, replace the EBCM.