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.
Code P026, Shorted Throttle Position Switch Circuit: Notes
Throttle position switch is part of ISC motor assembly. PCM provides a 5-volt reference signal on circuit No. 427. When throttle lever contacts ISC plunger, throttle switch closes. When throttle switch is closed, input voltage is low. Code P026 sets when PCM sees a TP sensor signal greater than 16 degrees (accelerator applied) but throttle switch remains closed.
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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.
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