PIP3394F

Bulletin No.: PIP3394F
Date: Apr-2013
Subject:
Duramax Diesel Injector Driver Codes
Models:
2004-2005 Chevrolet Kodiak, Silverado
2004-2005 GMC Sierra, Topkick
with 6.6 Engine (VIN 2 - RPO LLY)
This PI was superseded to update recommendations field. Please discard PIP3394E.
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern
Misfire, rough running, surge, chuggle, and possible MIL/SES light on.
Recommendation/Instructions
Do not replace fuel injectors for trouble codes P1223, P1226, P1229, P1232, P1235, P1238, P1241 or P1244. When these codes are set, there is either a wiring
concern between the Engine Control Module (ECM) and the Fuel Injection Control module (FICM), or a concern with the control module itself, (ECM/FICM). If
there is a concern on the injector driver circuits (open, short to ground or high resistance), it is possible to have a high injector balance rate.
1.
Diagnose all injector driver codes using the current SI diagnostics.
2.
If all SI diagnostics are inconclusive, inspect for wire chafes at the Fuel Injector Control Module (FICM) wiring harness brace. The wiring harness brace
is located 4 to 6 inches away from the FICM connectors. The wiring harness is nylon tied to the wiring harness brace. It may be necessary to remove
the nylon tie to inspect the harness. Repair any wire chafes following SI wire repair procedures. Insulate the harness with wiring conduit or a suitable
material so the wires will not chafe again.
3.
Also inspect the C107 (Silverado and Sierra) or C118 (Kodiak and Topkick) connector for wire chafes. The C107 (Silverado and Sierra) or C118
(Kodiak and Topkick) connector is found above the left (driver side) rocker cover. The wiring harness may relax and lay on top of the C107 (Silverado
and Sierra) or C118 (Kodiak and Topkick) support brace. This support brace is located right below the C107 (Silverado and Sierra) or C118 (Kodiak
and Topkick) connector. Repair any wire chafes following SI wire repair procedures. Insulate the harness with wiring conduit or a suitable material so
the wires will not chafe again.
4.
Use GMVIS to check the build date of the vehicle. If the vehicle is a 2005 light duty C/K truck, built between 3/03/05 and 3/15/05, refer to Inventory
Upgrade Bulletin number 05054. Inventory Upgrade Bulletin 05054 describes a possible coolant leak from the Coolant Surge Tank. The coolant may
wick into the engine wiring harness and induce injector driver codes.
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Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the
remaining steps do not need to be performed.
GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may
occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools,
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safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that
your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.
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