GM 57 Boost Control Solenoid Circuit Fault
How to read it
Code 57 reads as 5 flashes, pause, 7 flashes on the check-engine light. Jump terminals A and B on the ALDL connector with the key off, then turn the key on with the engine off and count the check-engine flashes.
New to flash codes? The How to Read GM OBD-I Codes with a Paperclip walks through the test and what the numbers mean. The general OBD-I guide covers the rest.
What does GM code 57 mean?
Boost Control Solenoid Circuit Fault
Common causes of 57
- Failed boost control solenoid
- Disconnected or cracked vacuum hoses to the solenoid
- Open or shorted solenoid wiring
- Faulty ECM boost output
How to fix 57
- Read codes with a paperclip jumper across ALDL terminals A and B
- Inspect wastegate hoses and solenoid vacuum lines for leaks
- Test the solenoid coil resistance and check it clicks with power
- Check wiring from the solenoid back to the ECM
- Replace the solenoid if it fails tests then retest boost
- Check the ECM output only after wiring tests clean
Source
Qualified source review
Sources and review
Review: qualified. Read the source limits below.
- GM OBD1 trouble codes, model and year page
live reference page (troublecodes.net)
Supports: code identity and GM meaning
Fetched directly from the linked model page. Single publisher, so the record is qualified, not verified.
https://www.troublecodes.net/GM/92-93_38SC/
Last updated 2026-09-19.
Report a correction for 57. Include your vehicle, the issue and a source if you have one.