Use this procedure to troubleshoot any suspect problems with the Injection Actuation Pressure Control Valve (IAPCV).
This procedure covers the following diagnostic codes:
- 42-05 Injector Actuation Valve open circuit
- 42-06 Injector Actuation Valve short to ground
Note: Do not use this procedure to troubleshoot an active 164-11 Injector Actuation Pressure system fault, unless you have been directed to this procedure from another section of this document.
The IAPCV is internal to the unit injector hydraulic pump. The IAPCV is a precision displacement control actuator. This actuator changes the pump outlet flow that is based on the control current that is supplied by the Electronic Control Module (ECM). The variable displacement unit injector hydraulic pump pressurizes only the amount of high-pressure oil that is needed.
The ECM software contains performance maps. The performance maps have a desired actuation pressure for every engine operating condition. The ECM sends a control current to the IAPCV. This signal creates an actual actuation pressure that matches the desired actuation pressure. If the actual actuation pressure does not match the desired actuation pressure, the ECM will increase the control current or the ECM will decrease the control current to the IAPCV in order to adjust pump outlet flow.
The following problems can cause a 42-05 diagnostic code:
- An open circuit in the wiring
- An open circuit in the IAPCV
- A short to ground on the return wire
The following problems can cause a 42-06 diagnostic code:
- The control wire has a short to the +Battery.
- The return wire has a short to the +Battery.
- A short circuit in the IAPCV
- A short to ground on the control wire
Illustration 1 g01121315
Schematic for the injection actuation pressure control valve
Illustration 2 g01121264
Left side view
(1) Connector for the IAPCV
(2) J2/P2 connectors
Illustration 3 g01121316
P2 terminations for the IAPCV