Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Circuit/System Testing
2006 Isuzu Ascender S, 5.3 M, 4WDSECTION Circuit/System Testing
WARNING: This page is about a different car, the 2008 Saab 9-7X. However, it is still accessible from the selected car via links, so may be relevant.
- Ignition OFF, disconnect the harness connector at the stop lamp switch.
- Ignition ON, vehicle in PARK, verify that a test lamp illuminates between the control circuit terminal F and ground.
- If the test lamp does not illuminate, test the control circuit for a short to ground or an open/high resistance.
- Ignition OFF, connect the harness connector at the stop lamp switch. Disconnect the harness connector at the automatic transmission shift lock actuator.
- Ignition OFF, test for less than 1.0 ohm between the ground circuit terminal A and ground.
- If greater than the specified range, test the ground circuit for an open/high resistance.
- Ignition ON, verify that a test lamp illuminates between the control circuit terminal B and ground.
- If the test lamp does not illuminate, test the control circuit for a short to ground or an open/high resistance.
- With the brake pedal pressed, verify that a test lamp illuminates between the control circuit terminal E and ground.
- If the test lamp does not illuminate, test the control circuit for a short to ground or an open/high resistance. If the circuit test normal, test or replace the stop lamp switch.
- With the brake pedal released, verify that a test lamp does not illuminate between the control circuit terminal E and ground.
- If the test lamp illuminates, test the control circuit for a short to voltage.
- If all circuits test normal, test or replace the automatic transmission shift lock actuator.
RENDER: 1.0x
NO RELATED
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.