P0618Alternative Fuel Control Module KAM Error
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- CARB treats gas-fuelled vehicles (CNG, LPG, also the gas mode of bi-fuel cars) like petrol cars up to model year 2018 and under an approved manufacturer plan afterwards. P0618 is meant for vehicles with a separate control module for the alternative fuel: it reports an error in that module's keep alive memory, which holds learned values while the ignition is off and loses them when power is cut – the gas counterpart of P0603. No manufacturer was found that uses P0618 this way; Roush's Ford propane conversions, for example, report a failed gas module as U0108. One Chrysler bulletin lists 'P0618' with the title of P061B – apparently a typo, not a second meaning. Expect lost adaptations; bi-fuel cars may switch to petrol. Check supply, fuse and ground of the gas module first.
- What you may notice
- Check engine or gas system warning light
- Switch to petrol, gas mode blocked (bi-fuel)
- Rough idle until values are relearned
- Often no symptoms
- Likely causes
- LikelyPower interruption at the gas module (battery disconnected, fuse, loose contact)
- PossiblePoor supply, ground or corrosion at the module (underbody mounting)
- PossibleSoftware or programming fault of the gas module
- RareInternal memory defect
- 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: €80 – €800
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.