Hello there is a service bulletin for the codes P0203 and p2149. It states that there could be a wire chafing problem for the fuel injector wiring harness rubbing through the alternator bracket. I would go over the harness and check the wires individually because there could be a break inside the wire coating.I'll give you the information for this issue.
Malfunction Indicator Lamp (MIL) Illuminated, Fuel Injector Driver Circuit DTCs and Cylinder Bank Shut Down DTCs, Reduced Engine Power (Repair Fuel Injector Control Module (FICM) Harness Chafed Wires) - (Aug 17, 2009)
|Subject:||Malfunction Indicator Lamp (MIL) Illuminated, Fuel Injector Driver Circuit DTCs P0201, P0202, P0203, P0204, P0205, P0206, P0207, P0208 and Cylinder Bank Shut Down DTCs P2146 or P2149, Reduced Engine Power (Repair Fuel Injector Control Module (FICM) Harness Chafed Wires)|
|Models:||2001-2004 Chevrolet Kodiak C4500/C5500 Series, Silverado Models|
|2001-2004 GMC Sierra Models, TopKick C4500/C5500 Series|
|Equipped with DuramaxTM Diesel Engine RPO LB7|
|2004-2005 Chevrolet Kodiak, Silverado Models|
|2004-2005 GMC Sierra Models, TopKick|
|Equipped with Duramax Diesel Engine RPO LLY|
Some customers may comment that the malfunction indicator lamp (MIL) is illuminated or intermittent and there is a significant reduction in engine power (limp home mode).
The scan tool may display one or more Injector Driver Circuit DTCs P0201, P0202, P0203, P0204, P0205, P0206, P0207 or P0208 and/or Cylinder Bank Shut Down DTCs P2146 or P2149 set as Current or in History.
This condition may be caused by the fuel injector control module (FICM) wiring harness protective conduit rubbing against the back of the alternator, the alternator bracket or the FICM harness retaining bracket. This may result in the conduit rubbing through, exposing the wires inside and chafing of the wire insulation then occurs.
- Turn ON the ignition, with the engine OFF.
- Observe the DTC information with the scan tool.
- If any of the above DTCs are set, then proceed to inspect the FICM wiring harness at the locations outlined in the following steps.
- Turn OFF the ignition and all accessories and allow the control modules to power down.
Note: For Silverado and Sierra models only perform Step 5.
- Remove the air cleaner outlet duct.
Important: DO NOT break off the tab on the electrical connectors.Disconnect the FICM electrical connectors (2) from the FICM (1).
Carefully bend up and backwards the FICM wiring harness electrical connectors (1) away from the FICM (4).
Note: Some of these chafes are very small, possibly the size of a pen tip, but could still cause injector circuit concerns.Inspect the wiring harness for chafing (3) that may result from rubbing at the back of the alternator (2), the alternator bracket or at the FICM harness retaining bracket.
If necessary, peel the tape from the area and look for ANY chafes into the wires.
|⇒||If chafing is observed and the conductive portion of the wire IS NOT damaged, apply electrical tape around the wire.|
|⇒||If chafing is observed and the conductive portion of the wire IS damaged, then refer to Splicing Copper Wire Using Splice Sleeves in Wiring Repairs in SI.|
Connect the electrical connectors to the FICM.Insulate the harness with suitable material such as conduit or heater hose to prevent a reoccurrence.
|⇒||If chafing IS NOT OBSERVED, then refer to the appropriate DTC Diagnostic procedures in SI.|
Note: For Silverado and Sierra models only perform Step 11.
IF THIS HAS HELPED YOU OUT PLEASE HIT THE ACCEPT BUTTON SO I RECEIVE CREDIT FOR HELP GIVEN. THANK YOU! ALL INFORMATION IS FOR EDUCATIONAL PURPOSES ONLY!