C0040 on RAM
Right Front Wheel Speed Sensor Circuit
C0040 on RAM vehicles indicates right front wheel speed sensor circuit. Au7o has documented this code across 1 RAM model — most commonly on 1500. 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 RAM range from $200 to $600, 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 RAM by Model
RAM 1500(1 issue)
- Front Wheel Bearing / Hub Assembly Failure (Humming/Growling Noise, ABS Light)2009-2018
4th-gen Ram 1500 front wheel bearing/hub assemblies wear out relatively early (some as low as ~50k miles), producing a humming or growling noise that rises with speed and changes with steering load. Because the wheel-speed sensor is integrated into the hub, a failing bearing frequently also sets an ABS/traction fault and light. It is one of the most common front-end noise complaints on these trucks.
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View C0040 across all makes →Frequently Asked Questions
What does C0040 mean on RAM?▼
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 RAM specifically, this code is documented across 1 model.
What causes C0040 on RAM vehicles?▼
Common causes on RAM: 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 RAM?▼
Repair costs on RAM range from $200 to $600, depending on the specific model and root cause.
Which RAM models have C0040 documented?▼
Au7o has documented C0040 on 1 RAM model: 1500.