Driver Demand Signal - Electronic Control Unit
The ECU is detecting an issue with the driver's demand signal input.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The engine's computer isn't getting the proper signals from the accelerator pedal position sensor, causing performance issues.
What the computer is actually seeing
The ECU expects a signal between 0.5 volts (minimum) and 4.5 volts (maximum) from the accelerator pedal position sensor when pressed. If it reads outside this range for a specific duration, the code sets.
What a healthy reading looks like
Expected signal voltage from accelerator pedal sensor should range between 0.5V and 4.5V during operation; idle should be approximately 0.5V.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 11. Inspect wiring and connectors related to the accelerator pedal position sensor for damage or corrosion. Decision Point: Are they in good condition? If no, repair or replace the damaged wiring/connectors.
- 22. Using a multimeter, check the accelerator pedal position sensor voltage at idle. Decision Point: Is voltage around 0.5V? If no, replace the sensor.
- 33. While monitoring the voltage, press the accelerator slowly and observe the increase in voltage. It should smoothly transition from 0.5V to 4.5V. Decision Point: Does it reach 4.5V? If no, replace the sensor.
- 44. If the sensor checks out, perform a ECU reset and check for codes again. Decision Point: Is the code still present? If yes, consider programming or replacing the ECU.
Common causes
- Faulty accelerator pedal position sensor
- Wiring issues between sensor and ECU
- Connector problems with the pedal position sensor
- ECU software glitches
Typical repair cost
$$$
Related codes
Frequently asked questions
Can I drive the vehicle with this code?
Yes, but expect reduced power performance. It’s advisable to fix it soon.
Will this code come back after repair?
If the root cause is fixed, it should not return.
Why does this code pair with SPN 1234?
Both codes relate to issues with the accelerator pedal position signal and may indicate similar problems.
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