Vacuum Reservoir Control Circuit/Open
The control circuit that drives the vacuum reservoir control valve (or vacuum pump motor) is open. The ECM cannot energise the actuator, so vacuum is no longer maintained on demand and consumers like brake booster, EGR or HVAC dampers may run out of vacuum.
Affected components
- Vacuum reservoir control valve
- Wiring harness
Common causes
- High likelihood: Open control wire
- Medium likelihood: Failed driver in the control module
- Low likelihood: Pin pushed back out of connector body
Diagnostic notes
- The malfunction indicator lamp may illuminate
Sources
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.