P2EB9 Reductant Injection Valve Circuit Range/Performance Bank 2 Unit 2

P2EB9 is the bank 2 twin of P2EAE: the circuit of the second DEF injector on the second exhaust bank works electrically, but its signal does not match a valve that opens and closes as it should. Bank 2 implies a separate exhaust line for the second cylinder bank, and unit 2 a further dosing point on that line. No manufacturer documents P2EB9 publicly. GM's 3.0 L Duramax LZ0 shows how such a test runs for bank 1 unit 2: it takes the second derivative of the injector current and fails when too few injections show the armature moving. Delphi's patent US11280245 describes the same kink detection. Open circuit, low and high on this injector are P2056 to P2058. Usual causes are crystal deposits, a sticking armature and corroded contacts; NOx emissions can then exceed the limits.

Likely causes

Symptoms

• Check engine lamp on
• DEF system warning
• Higher NOx emissions

Repair estimate

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

Parts involved

Related codes

References: gsi.ext.gm.com, patents.google.com, law.cornell.edu.