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.
2012 Cadillac Escalade EXTFACTORY OEM SERVICE PROCEDURE
Circuit/System Testing
WARNING: This page is about a different car, the 2008 Cadillac CTS. However, it is still accessible from the selected car via links, so may be relevant.
- Ignition OFF, disconnect the harness connector at the discrimination sensor.
- Ignition OFF, test for less than 5 ohms of resistance between the discrimination sensor ground circuit terminal 3 and ground.
- If greater than the specified value, test the circuit for a short to voltage and an open/high resistance. If the circuit tests normal, replace the PIDS module.
- Ignition ON, verify a test lamp illuminates between the discrimination sensor supply voltage circuit terminal 4 and ground.
- If the test lamp does not illuminate, test the circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the PIDS module.
- Ignition OFF, disconnect the harness connector at the PIDS module.
- Test for infinite resistance between the discrimination sensor signal circuit terminal 2 and ground.
- If less than infinite resistance, test the circuit for a short to ground.
- Ignition ON, test for less than 1 volt between the discrimination sensor signal circuit terminal 2 and ground.
- If greater than the specified value, test the circuit for a short to voltage.
- Ignition ON, test for less than 1 volt between the discrimination sensor low reference circuit terminal 1 and ground.
- If greater than the specified value, test the circuit for a short to voltage.
- Test for less than 1 ohm of resistance between the discrimination sensor low reference circuit terminal 1 and the PIDS module terminal 40.
- If greater than the specified value, test the circuit for an open/high resistance. If the circuit tests normal, replace the discrimination sensor.
- Test for less than 1 ohm of resistance between the discrimination sensor signal circuit terminal 2 and the PIDS module terminal 39.
- If greater than the specified value, test the circuit for an open/high resistance. If the circuit tests normal, replace the safing sensor.
- If all circuits test normal, replace the discrimination sensor.
- With a scan tool, clear DTCs.
- Verify DTC B009C is not set.
- If DTC is set, replace the PIDS module.
Factory Service Tools
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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.