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 Description
The control module Programmable Read Only Memory (PROM) contains data which is essential to the operation of the engine and transmission. When ignition is on, values in all of PROM memory locations are added together and compared to a calibrated checksum number. If these 2 numbers are not equal, DTC will be set. This test determines if any address locations have become corrupt. DTC will set when VCM is unable to correctly read data from EEPROM memory.
Use the Manual With the Right Hardware
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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.