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.
Diagnostic Aids
Perform this test when directed by QUICK TEST. This CIRCUIT TEST is intended to diagnose the following:
- MAF sensor.
- Wiring harness circuits (VPWR, PWR GND, MAF and MAF RTN).
- Powertrain Control Module (PCM).
To prevent replacement of good components, be aware the following non-EEC related areas may be cause of problem:
- Air cleaner element.
- Inlet air duct.
- Throttle body.
Code 26/159, retrieved during KOEO SELF-TEST, indicates voltage exceeded .7-volt test range. Code 26/159, retrieved during KOER SELF-TEST, indicates voltage is not within .2-1.5 volts operating range. Possible causes are faulty MAF sensor or PCM.
NO RELATED
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.