P0641 on Chevrolet
Sensor Reference Voltage "A" Circuit/Open
P0641 on Chevrolet vehicles indicates sensor reference voltage "a" circuit/open. Au7o has documented this code across 1 Chevrolet model — most commonly on TrailBlazer. The control module detected an open or out-of-range condition on the 5-volt sensor reference 'A' supply circuit that powers multiple drivability sensors. The reference voltage is missing or incorrect. Typical repair costs on Chevrolet range from $150 to $700, depending on the specific model and root cause.
Common Causes of P0641
- •Short or open in the 5V reference 'A' circuit
- •Shorted sensor pulling down the reference
- •Corroded/damaged connectors
- •Wiring chafe to power or ground
- •Internal PCM fault
P0641 on Chevrolet by Model
Chevrolet TrailBlazer(1 issue)
- Electronic Throttle Body / TAC System Fault — 'Reduced Engine Power' with P21352002-2009
The GMT360 TrailBlazer uses a drive-by-wire throttle actuator control system with dual redundant sensors in both the throttle body and the accelerator pedal. When the two throttle position signals disagree the PCM sets P2135 and drops the truck into Reduced Engine Power limp mode — the vehicle will barely accelerate, which is dangerous when it happens pulling into traffic. Usual root causes are an internally failed electronic throttle body, a corroded or loose crimp in the throttle body connector, or moisture intrusion in the harness. Related codes P0641 (5V reference) and P1523 (throttle closed position performance) show up alongside it.
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View P0641 across all makes →Frequently Asked Questions
What does P0641 mean on Chevrolet?▼
P0641 stands for "Sensor Reference Voltage "A" Circuit/Open." The control module detected an open or out-of-range condition on the 5-volt sensor reference 'A' supply circuit that powers multiple drivability sensors. The reference voltage is missing or incorrect. On Chevrolet specifically, this code is documented across 1 model.
What causes P0641 on Chevrolet vehicles?▼
Common causes on Chevrolet: Short or open in the 5V reference 'A' circuit, Shorted sensor pulling down the reference, Corroded/damaged connectors, Wiring chafe to power or ground, Internal PCM fault. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P0641 on a Chevrolet?▼
Repair costs on Chevrolet range from $150 to $700, depending on the specific model and root cause.
Which Chevrolet models have P0641 documented?▼
Au7o has documented P0641 on 1 Chevrolet model: TrailBlazer.