Code result
P26E4
Starter Relay B Circuit
Moderate severity
What it means
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.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Open coil in the relay
highOne of the most commonly reported causes for this code — check this first.
Broken control wire
mediumA plausible cause — test and verify before replacing parts.
Related help
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