| Subject: | Revised DTC P1404 | 
| Models: | 2002-2004 Chevrolet Silverado | 
| 2003-2004 Chevrolet Kodiak | 
| 2002-2004 GMC Sierra | 
| 2003-2004 GMC TopKick | 
| with 6.6L Diesel Engine (VIN 1 - RPO LB7) | 
This bulletin is being issued to revise Step 4 of DTC P1404 in the Engine Controls sub-section of the Service Manual. Please replace the current information in the Service Manual with the following information.
The following information has been updated within SI. If you are using a paper version of this Service Manual, please make a reference to this bulletin on the affected page.
The component to be tested is the EGR Vacuum Control Solenoid, NOT the EGR Vent Solenoid.
4  | 
 Important: Mark all disconnected vacuum hoses for proper installation if necessary. 
 Does the EGR vacuum control solenoid operate as described in the above test?  | --  | Go to Step 5  | Go to Step 9  |