P26EB
Alternative Fuel Control Module System Voltage
The alternative fuel control module reports a system voltage out of operating range. CNG, LPG, or hydrogen fuelling can be disabled until voltage is in spec.
- Check engine light: Yes
- Emissions related: No
- Repair difficulty: medium
Common causes
Ordered by how often each turns out to be the cause.
- Weak battery sags voltage under loadPossible
- Alternator output out of regulationPossible
Parts involved
- Alt Fuel Control Module
- Charging System
P26EB is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.