P1822
Internal Mode Switch B Circuit High Voltage
What it means
P1822. Internal Mode Switch B Circuit High Voltage. This Chevy-enhanced code applies to Impala, Malibu, Monte Carlo, Silverado, Sierra.
Findings, check these first
- Faulty internal mode switch inside the transmission
- Open in IMS signal B circuit between TCM and the switch
- Misadjusted shift cable holding the switch between detents
- Corroded AT inline connector or control solenoid valve assembly pins
- Faulty transmission control module input
Standard procedure
- Observe IMS A/B/C/P parameters in each shifter detent with a Tech2 scan tool
- Verify shift cable adjustment before opening the transmission
- Test IMS signal B circuit for opens and high resistance
- Inspect the AT inline connector and TEHCM pins for metallic debris
- Replace the IMS or control solenoid valve assembly if circuits test normal
Look up another code
Press / to jump to the box. Chevy-enhanced powertrain, body, chassis and network codes.
Sources and review
Review: no source links are recorded for this entry.
Last updated 2026-09-13.
Report a correction for P1822. Include your vehicle, the issue and a source if you have one.