OBD-I Codes List

GM 67 A/C Pressure Sensor Circuit Fault

Make
GM (1982-1995)
Category
Powertrain - Computer and Auxiliary Controls
Severity
Check Engine Light

How to read it

Code 67 reads as 6 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 67 mean?

A/C Pressure Sensor Circuit Fault

Common causes of 67

  • Failed A/C pressure sensor
  • Shorted or open sensor wiring
  • Corroded sensor connector
  • Faulty 5 volt reference from the ECM

How to fix 67

  1. Read codes with an ALDL scan tool
  2. Backprobe the sensor for 5 volt reference and ground
  3. Check the signal wire for shorts or opens
  4. Compare the sensor value with gauge pressure
  5. Replace the sensor if reference is good but output is wrong
  6. Clear the code and run the A/C to verify

Source

Qualified source review

Sources and review

Review: qualified. Read the source limits below.

  • GM and Chevrolet OBD1 Trouble Codes (ALDL Fault Code List)

    live reference page (troublecodes.net)

    Supports: code identity and GM meaning

    Fetched directly. Single publisher, so the record is qualified, not verified. Causes and check order are curator-written from the circuit the code names.

    https://www.troublecodes.net/gm/

Last updated 2026-09-19.

Report a correction for 67. Include your vehicle, the issue and a source if you have one.

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