OBD-II reference

All 9.533 generic OBD-II codes, explained in detail.

Causes, inspection steps and sources — a comprehensive DIY archive. Created and maintained with love for the detail. Good luck and have fun!

Powertrain generic / SAE

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.

SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number6 / E4

Possible causes

  • Open coil in the relay high
  • Broken control wire medium

Inspection / repair

  • Difficulty: easy
  • DIY: possible
  • Estimated cost: 50–300 €
  • Estimated time: 0.3–1.5 h
  • Component: starter relay b
  • Component: wiring harness
  • MIL / check engine light

Sources

References

How to read OBD-II codes

The first letter names the vehicle system, the second digit distinguishes generic from manufacturer-specific, the remaining digits group fault area and number.

PPowertrain: engine, transmission, emissions
BBody: chassis trim, comfort, interior
CChassis: suspension, brakes, steering
UNetwork: CAN, control modules, communication