P305F: Dual battery control module performance (Chevrolet Malibu eAssist)
P305F dual battery control module performance
Severity: Severity not verified — if the car runs badly, have it inspected
The GM bulletins read describe the code and a diagnostic tip but do not say whether the car is safe to drive.
It gets more serious if:
- Stop: Stop and have the car towed if there is smoke or a burning smell from under the hood. GM opened a field investigation into underhood smoke or burning odor with P305F or P058D.
P305F in short
On the Chevrolet Malibu (and Impala), GM defines P305F as Dual Battery Control Module Performance. GM tells technicians not to replace the engine computer first, but to check for a loose or unsecured ground wire at the auxiliary battery cables. Smoke or a burning smell with this code means stop driving.
P305F is a General Motors code. GM bulletins list it on the 2014-2016 Malibu, which has two 12-volt batteries and a control module that switches them in and out to support vehicle loads and charging.
GM bulletin PI1412A says the cause can vary and gives a diagnostic tip: inspect for an unsecured ground wire at the auxiliary battery cables. GM bulletin PIE0463 separately asked the field for reports of underhood smoke or burning odor with P305F or P058D on 2014-2018 Impala and Malibu.
Because the code can come from cabling as well as the module, swapping the control module or engine computer first is not the recommended path.
Pick your make
P305F is a manufacturer-specific code: its meaning depends on who built the car.
Other makes: meaning not verified. Check with a scan tool that reads manufacturer definitions.
Most likely causes
Cause 1: Unsecured ground wire at the auxiliary battery cables
Supported by vehicle data- Why it ranks here
- GM PI1412A is a diagnostic tip to inspect for an unsecured ground wire at the auxiliary battery cables when P305F is set.
- What would change this
- Rises if a ground or battery cable is found loose. Falls if all cable connections are tight.
Cause 2: Dual battery control module fault
Possible — needs testing- Why it ranks here
- The code name points at this module, but the GM bulletins read give cabling as the first check, not the module itself.
- What would change this
- Rises if cabling checks good and the code returns. Falls if a loose connection is found.
Cause 3: Underhood wiring or connection overheating (smoke or burning smell)
Possible — needs testing- Why it ranks here
- GM PIE0463 asked for field reports of smoke or burning odor with P305F or P058D, but the summary does not state the cause.
- What would change this
- Rises with a burning smell or visible smoke. Falls if neither is present.
What to test first
Start at step 1. Each result tells you what it means and where to go next.
Step 1: Ask whether there has been smoke or a burning smell from under the hood. If yes, stop driving and have the car towed.
IfSmoke or a burning smell
It meansDo not drive; have it inspected.
Points to: Underhood wiring or connection overheating (smoke or burning smell)
IfNo smoke or smell
It meansHave the battery cable and ground connections checked by a shop.
Step 2: Have a shop inspect the main and auxiliary battery cable ground connections and the engine harness near the battery tray.
Warning:Battery cables on this car sit near an eAssist hybrid system; leave work on them to a trained technician.
IfA loose or unsecured ground is found
It meansSecure it and re-test.
Points to: Unsecured ground wire at the auxiliary battery cables
IfAll connections are good and the code returns
It meansModule diagnosis is next.
Symptoms
- Check engine light with the P305F code
- Smoke or burning smell from under the hood Gets more serious: stop and have it checked.
How to fix
On your vehicle
ChevroletYour car
2014–2018 · Malibu
Supported by vehicle dataGM bulletins PI1412, PI1412A and PIE0463 cover P305F on the Malibu: check the auxiliary battery ground cables first, and treat smoke or a burning smell as a stop. Whether the bulletin is still current is not verified.
2014–2018 · Impala
Supported by vehicle dataGM bulletin PIE0463 asked for field reports of smoke or burning odor with P305F or P058D on the Impala. Whether the bulletin is still current is not verified.
PI1412Status unverified
P305F Dual Battery Control Module Performance
2014–2015malibu · NHTSA 10113540
Diagnostic tip for P305F.
We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.
PI1412AStatus unverified
P305F diagnostic tip, unsecured ground wire
2014–2016malibu · NHTSA 10116909
Inspect for an unsecured ground wire at the auxiliary battery cables.
We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.
PIE0463Status unverified
Smoke or burning odor with P305F or P058D
2014–2018malibu, impala · NHTSA 10137614
Engineering request for field reports; superseded by PIE0463A, which ends the request.
We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.
Related codes
No curated relationships for P305F yet.
P305F questions
Should I replace the engine computer for P305F?
GM tells technicians to inspect for loose grounds and cables first rather than replace the engine computer.
Sources and review
- PI1412: P305F Dual Battery Control Module Performance
- PIE0463: smoke or burning odor with P305F or P058D
- PI1412A: P305F diagnostic tip, unsecured ground wire
- NHTSA complaint ODI 11408334: 2015 Chevrolet Malibu
- NHTSA complaint ODI 11390741: 2015 Chevrolet Malibu
- Last reviewed
- Written by
- Saurabh K.
- Editorial review
- Pending
- Technician review
- Technician review pending
This page explains what a code usually means; it is not a substitute for a professional inspection. How we source and review · Report an error