P26E6Starter Relay B Circuit High
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- P26E6 reports a short to positive on the control line of starter relay B. GM tests for it while its driver for the tandem starter pinion relay is off: if the line still shows 0.5 Ohm or less toward a power source for 40 out of 50 checks taken every 50 ms, with the engine stopped and at least 11 V available, the code is stored as type B. The danger of this fault is a relay that is energised without a command, so the pinion could be pushed into the ring gear. The diagnostic appears in GM's 2018 and 2023 tables with the same thresholds. P26E4 and P26E5 cover open and grounded circuits.
- What you may notice
- Check engine light
- Stop-start disabled
- Starter noise or grinding without a start command
- Likely causes
- LikelyRelay B control wire shorted to a battery-powered wire, e.g. under the battery tray
- PossibleRelay B internally fed or contacts welded
- RareEngine module driver output not switching off
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €50 – €800
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.