P26E4
Starter Relay B Circuit
The control circuit for the secondary starter relay (used on twin-starter heavy diesels or stop-start systems with a dedicated stop-start starter) returns no usable signal.
- Check engine light: Yes
- Emissions related: No
- Repair difficulty: easy
Common causes
Ordered by how often each turns out to be the cause.
- Open coil in the relayCommon
- Broken control wirePossible
Parts involved
- Starter Relay B
- Wiring Harness
P26E4 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.