What does P1108 mean on a Ford?

P1108. Dual Alternator Battery Lamp Circuit Malfunction. Applies to Super Duty and E-Series with dual alternator packages.

What causes P1108 on a Ford?

Burned-out battery warning lamp breaking the excite circuit Open lamp circuit wiring Corroded cluster connector Failed lamp driver Aftermarket cluster or LED swap without proper load

How do I fix P1108 on a Ford?

Confirm the battery lamp illuminates with key on, engine off Check the lamp and its circuit continuity Inspect cluster connections Restore factory lamp loading if LEDs were fitted Repair the circuit so the alternators excite properly

Code

P1108

Dual Alternator Battery Lamp Circuit Malfunction

Category: Powertrain - Computer and Auxiliary Controls
Severity: Check Engine Light
Applies to: Super Duty and E-Series with dual alternator packages
Related: P0562 Charging System Voltage Low on OBD Codes List

Findings, check these first

Burned-out battery warning lamp breaking the excite circuit
Open lamp circuit wiring
Corroded cluster connector
Failed lamp driver
Aftermarket cluster or LED swap without proper load

Standard procedure

Confirm the battery lamp illuminates with key on, engine off
Check the lamp and its circuit continuity
Inspect cluster connections
Restore factory lamp loading if LEDs were fitted
Repair the circuit so the alternators excite properly

Code lookup

Type a code above, or start from a symptom or a common code.

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Sources and review

Review: qualified. Read the source limits below.

OBDII.pro: P1108 Ford definition
live reference page (obdii.pro)
Supports: Ford-family meaning for P1108: Dual Alternator Battery Lamp Circuit Malfunction
Fetched directly. obdii.pro is a publisher independent of the engine-codes family.

Last updated 2026-09-05.

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