Throttle/Pedal Position Sensor/Switch B Circuit Intermittent
What it means
The engine computer has detected brief dropouts or sudden jumps in the B signal from the throttle position sensor or accelerator pedal sensor. The fault is usually a loose connector or damaged wire that moves with vibration, and it can cause sudden power loss that then returns.
Symptoms4
- Check engine light that comes on and goes off.
- Sudden, temporary power loss or limp mode that comes and goes.
- Stumbling or jerking during acceleration.
- The fault may clear after turning the engine off and on.
Possible causes5
- Loose connector or a spread terminal inside it with poor contact.
- Damaged wire inside the harness that opens with vibration or heat.
- Terminal corrosion from moisture.
- Intermittent wear in the sensor's internal track.
- Failed electronic throttle body assembly or pedal sensor.
How to diagnose5
- Watch the B signal on a scan tool or graph it with an oscilloscope while wiggling the wiring and connector.
- Check terminal tension with a suitable test tool and look for any spread terminal.
- Inspect the harness routing for chafing near the engine or at bend points.
- Move the pedal or throttle slowly through the full range to find a dropout at a certain position.
- Review the freeze frame data to see the conditions when the code set.
How to fix5
- Tighten or replace the terminals, or replace the whole connector.
- Repair the damaged wire and secure the harness to prevent chafing.
- Clean corroded terminals and protect them from moisture.
- Replace the pedal sensor or throttle body assembly if the dropout is proven inside it, then perform the relearn.
- Clear the codes, then road test on varied roads and confirm the code does not return.
Repair cost
In Saudi riyals; the highlighted part is the expected range for this fault.
The cost is usually low because the cause is a connector or wire, but it rises if the dropout is inside the pedal sensor or throttle body assembly.
Prices are rough estimates for common cars at independent workshops and vary with the car and the source of the part.
Prices last updated: September 2026
Frequently asked questions
Why is this fault hard to find in the workshop?
Because it only shows up with vibration, heat or at a certain pedal position, so the technician must watch the signal while moving the wiring or during a drive.
Does replacing the sensor always fix it?
No. If the cause is a loose terminal in the connector, the code will return even with a new sensor.
Is it dangerous to drive with this code?
Sudden power loss can be dangerous when overtaking or on highways, so drive with care and repair it soon.
This guide is for information only and does not replace an inspection by a qualified technician. If the fault involves brakes, steering, engine temperature, electrics or refrigerant, do not attempt the repair yourself.
Report a mistake
Spotted something inaccurate? Tell us and we will review and correct it.
Report received — thank you
This is your private tracking link. It shows the status and our reply as soon as it is posted.
The link is saved in this browser only.