One problem related to wiring has been reported for the 2003 Chevrolet 1500. The most recently reported issues are listed below.
Reduced engine power. This has been occurring off and on for about 9 months, have taken it to dealer multiple times and replaced everything that was said would fix the problem. The problem still occurs even after replacing: accelerator and receiver on throttle body as well as checking wiring harness for issues. Essentially, the vehicle will lose the function of the accelerator without warning at any given time during the use of the vehicle. The dealer has told me that they don't have any idea why it still is having this issue. . . The other day the vehicle was being driven and reduced engine power mode set in and at the same time the power steering went out. Thought the power steering going out at the same time was a one time deal but it happened again the very next day. The vehicle had this issue on the highway the other day and nearly caused an accident. It is shocking that there are not thousands of complaints with this same issue, if you look up forums on this topic there are over 200,000 threads on this very issues. There are thousands of forum complaints about reduced engine power and how people have spent $1000 plus at the dealer and the issue still persists. The drive by wire functionality instead of using a throttle cable seems to be having issues that even gm doesn't have an answer for. Would appreciate any looking into on this subject.