OBD-II code · Powertrain (generic)
P05F6 Exhaust Aftertreatment Power Relay Control Circuit Stuck On
The aftertreatment power relay is stuck on - aftertreatment electronics stay powered after key-off, draining the battery.
Is it safe to drive with P05F6?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyRelay welded closed
- Less likelyCarbon or debris buildup preventing free movement
- Less likelyComponent wear with age - mechanical play
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Often, with basic tools
- Typical labour
- 0.5–1.8 h
- Emissions test
- Likely to fail
- Parts involved
- Aftertreatment Power Relay
Related codes
- P05F3Exhaust Aftertreatment Power Relay Control Circuit Open
- P05F4Exhaust Aftertreatment Power Relay Control Circuit Low
- P05F5Exhaust Aftertreatment Power Relay Control Circuit High
- P05F7Exhaust Aftertreatment Power Relay Control Circuit Stuck Off
- P05F8Reductant Heater Control Module Performance
- P05F9Stop-Start Status Signal Circuit
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.