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.
Test 17: Entrance/Exit Light Circuit
Using Harness Adapter (210 589 01 63 00), connect Breakout Box (129 589 00 21 00) to combination control module. Measure voltage between terminals No. 27 and 75 at breakout box. When any door is opened, battery voltage should exist. When all doors are closed, less than one volt should exist. If voltage is as specified, entrance/exit light circuit is okay at this time. If voltage is not as specified, check the following and repair as necessary:
- Check wiring.
- Check door switches.
- Check combination control module.
- Check Pneumatic System Equipment (PSE) control module.
- CAN data line. See WIRING DIAGRAMS in the DOOR LOCKS - PNEUMATIC & POWER article.
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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.