C1233 on Chevrolet

On Chevrolet and Buick, right front wheel speed sensor circuit open or shorted

Severity not verified — if the car runs badly, have it inspected

The ABS and traction control lamps stay on and the system may cycle unexpectedly, but none of our sources rate how long driving is safe; the normal brakes still work when ABS is off.

It gets more serious if:

  • Inspect soon: Get it checked soon if the ABS cycles during normal braking or the car pulls to one side when you brake. An Impala owner reports both.

Safety-critical system: explanation only, no DIY steps. Source: how we rate severity

This page covers only what differs on Chevrolet. For what C1233 means, the ranked causes and the test order, see the C1233 guide.

What's different on Chevrolet

Chevrolet

  • 2001–2003 · Impala

    Supported by vehicle data

    GM bulletin 032503 lists C1233 for the 2001-2003 Impala; two owners of 2002 cars store it with ABS and traction lamps on.

  • 2001–2003 · Monte Carlo

    Supported by vehicle data

    GM bulletin 032503 lists C1233 among front wheel speed sensor codes.

  • 2001–2003 · Venture

    Supported by vehicle data

    GM bulletin 032503 lists C1233 among front wheel speed sensor codes.

  • 032503 (chevrolet)Status unverified

    Front wheel bearing replacement for front wheel speed sensor codes

    2001–2003impala, monte-carlo, venture · NHTSA 10001865

    Replace the front wheel bearing when the ABS, traction control or service engine soon light is on with front wheel speed sensor codes P1221, P1222, P1225, P1226, C1232 or C1233.

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

Sources and review

  1. GM bulletin 032503: front wheel bearing replacement for front wheel speed sensor codes — General Motors via NHTSA
  2. NHTSA complaint ODI 10224551 (2002 Chevrolet Impala, EBCM code list) — NHTSA Office of Defects Investigation (consumer complaint)
  3. NHTSA complaint ODI 10839606 (2002 Chevrolet Impala, C1233) — NHTSA Office of Defects Investigation (consumer complaint)
Last reviewed
Written by
Saurabh K.
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This page explains what a code usually means; it is not a substitute for a professional inspection. How we source and review · Report an error

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