Circuit/System Testing

NOTE: Refer to SIR SERVICE PRECAUTIONS .
When removing connectors, inspect for damage or corrosion. Damage or corrosion in the following requires repair or replacement of the affected component/connector:

The front end sensor
The SDM module
The front end sensor wiring harness connector
The SDM wiring harness connector

Ignition OFF, disconnect the appropriate front end sensor connector.
Disconnect the harness connector at the SDM.
Ignition ON, test for less than 1 volt between the front end sensor signal circuit terminal B and ground.
- If greater than the specified range, test the circuit for a short to voltage.
Ignition ON, test for less than 1 volt between the appropriate front end sensor low reference circuit terminal A and ground.
- If greater than the specified range, test the circuit for a short to voltage.
Test for infinite resistance between the front end sensor signal circuit terminal B and ground.
- If less than infinite resistance, test the circuit for a short to ground.
Test for less then 1 ohm between the following front end sensor signal circuit terminals.
- Right front end sensor terminal B and SDM harness connector terminal 37.
- Left front end sensor terminal B and SDM harness connector terminal 36.
  - If greater than the specified range, test the circuit for an open/high resistance.
Test for less then 1 ohm between the following front end sensor low reference circuit terminals.
- Right front end sensor terminal A and SDM harness connector terminal 39.
- Left front end sensor terminal A and SDM harness connector terminal 38.
  - If greater than the specified range, test the circuit for an open/high resistance.
If all circuits test normal, replace the appropriate front end sensor.
Reconnect all SIR components. Ignition ON, with a scan tool clear and recheck for DTCs.
- If the front end sensor DTC returns and is current, replace the SDM.