Powertrain, generic (extended)

P2AF2 Starter Relay C Control Circuit/Open

Check engine lightOn
EmissionsNot relevant
Drive cycleRequired
Limp modeNo

P2AF2 reports an open or otherwise faulty control line for a third starter relay. Such a relay appears where cranking is split across several switching stages, for instance on stop-start engines. No manufacturer documents P2AF2 publicly. The nearest documented user of relay C is Stellantis, which calls it Starter Relay 3: on Jeep and RAM stop-start models it is the power control relay that cuts the main battery off from the auxiliary one during an auto-start, yet published bulletins only cover its stuck codes P2AF5 and P2AF6. As an analogy for the circuit test, GM treats its tandem starter pinion relay output (P26E4) as open at 200 kΩ or more between signal and ground, after 40 failures in 50 samples of 50 ms, Type B. Shorts to ground and to voltage are P2AF3 and P2AF4.

Likely causes

Broken control wire or unplugged relay connector
Open relay coil
Blown fuse or missing supply to the relay coil
Faulty output driver in the control module

Symptoms

  • Stop-start function disabled
  • Occasional or permanent no-crank
  • Warning lamp depending on manufacturer

Repair estimate

DifficultyMediumDIY possible
Parts and labour€20–400
Time0.3–2 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

starter relay cwiring harnessecm

Related codes

P2AF3P2AF4P2AF5P2AF6P2AF7P0615P26E4

References: law.cornell.edu, gsi.ext.gm.com, static.nhtsa.gov.