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.
IMS (Internal Mode Switch) States
A/B/C/P: Displays LOW or HI for the state of each of the four inputs from the IMS. LOW displayed indicates a low voltage signal (0 volts) being monitored at the PCM. HI displayed indicates a high voltage signal (B+) being monitored at the PCM.
TCC Brake Switch: Displays ON when the brake pedal is depressed and the brake switch contacts close. Displays OFF when the brake pedal is released and the brake switch contacts open.
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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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.