What are the common causes of C0022?

A failed brake booster solenoid. An open or short in the brake booster solenoid wiring. Corrosion at the solenoid connector. Low vacuum supply to the brake booster. A blocked or kinked brake vacuum hose.

Inspect the brake booster solenoid wiring and connector. Check vacuum supply and the brake vacuum hose for blocks or kinks. Test the brake booster solenoid and replace it if it fails. Check the brake booster itself for a leak. Test the booster solenoid relay if the solenoid circuit is good. Clear the code and retest.

C0022

Brake Booster Solenoid

System: Chassis control (C code)
Lamp: Chassis Warning Light
Category: Chassis

What it means

C0022 means Brake Booster Solenoid.

Where it lives

For C0022, the description names the solenoid as the part involved.

Check these first

A failed brake booster solenoid
An open or short in the brake booster solenoid wiring
Corrosion at the solenoid connector
Low vacuum supply to the brake booster
A blocked or kinked brake vacuum hose

What to do next

Inspect the brake booster solenoid wiring and connector
Check vacuum supply and the brake vacuum hose for blocks or kinks
Test the brake booster solenoid and replace it if it fails
Check the brake booster itself for a leak
Test the booster solenoid relay if the solenoid circuit is good
Clear the code and retest

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Updated

Generic SAE J2012 definition. Last updated 2026-10-10.