C0040 on Pontiac
Right Front Wheel Speed Sensor Circuit
C0040 on Pontiac vehicles indicates right front wheel speed sensor circuit. Au7o has documented this code across 1 Pontiac model — most commonly on Grand Am. This is a brake/ABS-system code. The right front wheel speed sensor measures how fast that wheel is rotating and feeds that data to the anti-lock brake, traction control, and stability control systems. C0040 means the ABS module found an electrical problem in the right front wheel speed sensor circuit — for example an open circuit, a short, or a signal that is missing or out of range. You'll normally see the ABS and traction/stability lights come on, and those systems may shut off temporarily while your regular brakes keep working. Typical repair costs on Pontiac range from $250 to $500, depending on the specific model and root cause.
Common Causes of C0040
- •Failed right front wheel speed sensor
- •Damaged, corroded or unplugged sensor wiring/connector
- •Damaged or rust-clogged tone/reluctor ring
- •Excessive air gap between sensor and tone ring
- •Wheel bearing wear affecting an integrated sensor
- •Water intrusion or corrosion at the connector
- •Faulty ABS control module (less common)
C0040 on Pontiac by Model
Pontiac Grand Am(1 issue)
- Front Wheel Hub Bearing Premature and Repeat Failure1999-2005
The sealed front hub bearing assemblies, which also house the ABS wheel-speed sensors, wear out prematurely and repeatedly on this generation — owners report replacing the same corner two or three times within a few years. As the bearing develops play, the integrated sensor signal drops out and the ABS, TRAC OFF, and SERVICE VEHICLE SOON lights come on, and a badly worn bearing left unaddressed risks wheel looseness. Flexing front sensor harness wires breaking at the strut are a common secondary trigger for the same warning lights.
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What does C0040 mean on Pontiac?▼
C0040 stands for "Right Front Wheel Speed Sensor Circuit." This is a brake/ABS-system code. The right front wheel speed sensor measures how fast that wheel is rotating and feeds that data to the anti-lock brake, traction control, and stability control systems. C0040 means the ABS module found an electrical problem in the right front wheel speed sensor circuit — for example an open circuit, a short, or a signal that is missing or out of range. You'll normally see the ABS and traction/stability lights come on, and those systems may shut off temporarily while your regular brakes keep working. On Pontiac specifically, this code is documented across 1 model.
What causes C0040 on Pontiac vehicles?▼
Common causes on Pontiac: Failed right front wheel speed sensor, Damaged, corroded or unplugged sensor wiring/connector, Damaged or rust-clogged tone/reluctor ring, Excessive air gap between sensor and tone ring, Wheel bearing wear affecting an integrated sensor. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix C0040 on a Pontiac?▼
Repair costs on Pontiac range from $250 to $500, depending on the specific model and root cause.
Which Pontiac models have C0040 documented?▼
Au7o has documented C0040 on 1 Pontiac model: Grand Am.