Open or high-resistance wire in the 5-volt reference circuit to the TP sensor; Short to ground on the 5-volt reference wire; Faulty throttle position sensor internally shorting the reference voltage; Corroded or loose electrical connector at the TP sensor or PCM; Failed PCM voltage regulator or internal driver for the 5-volt reference; Chafed or damaged wiring harness causing intermittent loss of voltage

DTC codes / GM codes / P1295

P1295 · GMLoss Of 5 Volts To TP Sensor

Q: What does code P1295 mean?

Loss Of 5 Volts To TP Sensor. P1295 on a GM vehicle means the powertrain control module (PCM) has detected a loss of the 5-volt reference voltage supplied to the throttle position (TP) sensor circuit. The PCM monitors this reference line and sets the code when the voltage drops below a calibrated threshold, which prevents it from accurately reading throttle position.

P1295 on a GM vehicle means the powertrain control module (PCM) has detected a loss of the 5-volt reference voltage supplied to the throttle position (TP) sensor circuit. The PCM monitors this reference line and sets the code when the voltage drops below a calibrated threshold, which prevents it from accurately reading throttle position.

SystemPowertrain

Code typeGM specific

SeverityMedium

Fix difficultyIntermediate

AreaFuel and air metering (injector circuits)

Symptoms you may notice

Illuminated check engine light, often with no other noticeable symptoms
Reduced engine power or limp mode, limiting acceleration
Hesitation or stumble when pressing the accelerator
Erratic or surging engine speed at idle
Poor fuel economy or increased emissions
In some cases, the engine may stall or refuse to start

Common causes, most likely first

Open or high-resistance wire in the 5-volt reference circuit to the TP sensor
Short to ground on the 5-volt reference wire
Faulty throttle position sensor internally shorting the reference voltage
Corroded or loose electrical connector at the TP sensor or PCM
Failed PCM voltage regulator or internal driver for the 5-volt reference
Chafed or damaged wiring harness causing intermittent loss of voltage

How to diagnose and fix it

Connect a scan tool and record freeze-frame data to confirm the code and check for other stored codes
Inspect the TP sensor connector and wiring for corrosion, loose pins, or obvious damage
Measure the 5-volt reference voltage at the TP sensor connector with the key on, engine off
If voltage is low, disconnect the TP sensor and recheck the reference voltage at the connector to isolate the sensor from the circuit
Check for continuity and resistance in the reference wire between the TP sensor and PCM, looking for opens or shorts to ground
If the circuit tests good, substitute a known-good TP sensor and clear the code to see if it returns
If the reference voltage remains low with the sensor disconnected and wiring intact, diagnose the PCM and repair or replace as needed

What a 5-volt reference loss really means

The 5-volt reference is shared by multiple sensors on many GM engines, so a shorted sensor on the same circuit can cause P1295 even if the TP sensor itself is fine.
A common misdiagnosis is replacing the throttle position sensor when the actual fault is a rubbed-through wire in the harness near the throttle body or intake manifold.
Intermittent P1295 codes often appear after engine work where the harness was disturbed, so always inspect for stretched or pinched wires before condemning parts.
The PCM may set P1295 along with other sensor codes if the shared reference voltage is pulled down, so check all related codes before assuming a single sensor failure.
A failing PCM is rare but possible; confirm power and ground integrity to the PCM before replacing it, as poor grounds can mimic a reference voltage fault.

Can I keep driving with P1295?

You can drive the vehicle to a repair shop if the engine runs normally and the check engine light is the only symptom, but avoid heavy acceleration or towing. If the engine enters limp mode or stalls, stop driving and have the vehicle towed to prevent unsafe conditions.

Tools that help

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Guidance is general and written for GM vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.