P0122

High Severity

Throttle Position Sensor A Circuit Low

Fuel System

What Does P0122 Mean?

TPS voltage is below minimum threshold. The ECM cannot determine throttle position accurately.

Common Fix

Replace TPS

Estimated Cost (DIY)

$20 - $100

Symptoms

  • ⚠️Engine stuck at idle
  • ⚠️No acceleration response
  • ⚠️Limp mode
  • ⚠️Check engine light

Related Symptoms

Check engine light on

Common Causes

Faulty TPSlikely
Wiring short to groundpossible
Bad TPS connectorpossible
ECM driver faultunlikely

How to Diagnose P0122

  1. 1Check TPS connector and wiring
  2. 2Measure TPS signal voltage
  3. 3Check 5V reference wire
  4. 4Replace TPS

OEM Diagnostic Flowchart

Scroll to load technician if/then branches.

Read live data and freeze frame for P0122 to pinpoint the cause before buying parts.

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Related Resources

Repair guides, symptom pages, and wiring diagrams related to P0122.

OEM Manual Evidence

Browse →
2013 GMC Truck Yukon XL Denali AWD V8-6.2L A L L Diagnostic Trouble Codes ( DTC )OEM Manual

A L L Diagnostic Trouble Codes ( DTC ) — 2013 GMC Truck Yukon XL Denali AWD V8-6.2L Service Manual | Operation CHARM Operation CHARM : Car...

2013 GMC Truck Yukon XL Denali 2WD V8-6.2L A L L Diagnostic Trouble Codes ( DTC )OEM Manual

A L L Diagnostic Trouble Codes ( DTC ) — 2013 GMC Truck Yukon XL Denali 2WD V8-6.2L Service Manual | Operation CHARM Operation CHARM : Car...

2013 GMC Truck Yukon XL 4WD V8-6.0L A L L Diagnostic Trouble Codes ( DTC )OEM Manual

A L L Diagnostic Trouble Codes ( DTC ) — 2013 GMC Truck Yukon XL 4WD V8-6.0L Service Manual | Operation CHARM Operation CHARM : Car repair...

2013 GMC Truck Yukon XL 4WD V8-5.3L A L L Diagnostic Trouble Codes ( DTC )OEM Manual

A L L Diagnostic Trouble Codes ( DTC ) — 2013 GMC Truck Yukon XL 4WD V8-5.3L Service Manual | Operation CHARM Operation CHARM : Car repair...

Related Symptoms

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Check engine light onSymptom Hub

A check-engine light is a graph entry point into code pages, symptom-specific diagnosis, and the exact repair categories most often associated with those failures.

Exact Vehicle Hubs

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2013 Gmc Truck Yukon Xl 4wd V8 5.3l Repair HubManual

Open the exact vehicle hub grounded by OEM manual evidence related to P0122.

2013 Gmc Truck Yukon Xl 4wd V8 6.0l Repair HubManual

Open the exact vehicle hub grounded by OEM manual evidence related to P0122.

2013 Gmc Truck Yukon Xl Denali 2wd V8 6.2l Repair HubManual

Open the exact vehicle hub grounded by OEM manual evidence related to P0122.

2013 Gmc Truck Yukon Xl Denali Awd V8 6.2l Repair HubManual

Open the exact vehicle hub grounded by OEM manual evidence related to P0122.

Related Codes

P0120: Throttle Position Sensor A CircuitRelated

General fault in the TPS circuit. The TPS tells the ECM how far the throttle is open.

P0121: Throttle Position Sensor A Range/PerformanceRelated

The TPS reading does not match expected values based on MAP, RPM, and other inputs. Erratic readings indicate a worn TPS.

P0123: Throttle Position Sensor A Circuit HighRelated

TPS voltage is above maximum expected. ECM sees the throttle as more open than it actually is.

Frequently Asked Questions

Why wont my car accelerate with P0122?
The ECM thinks the throttle is fully closed, so it limits engine power. A new TPS usually fixes this immediately.
Can I drive in limp mode?
You can drive slowly to get home or to a shop, but speed is limited. Do not drive far in limp mode.

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