My 03 Duramax just died/quit going down the road today just like you switched the key off. Pulled code and it is U1800. Failure to communicate with fuel injector control module. Anyone had this before and what was the fix? checked fuses relays and all wires are good. Is my FICM toast? Thanks!!!
U1800
- Thread starter Zmanhaus
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It’s been a while since I messed with an LB7, but check the harness at the alternator bracket. Notorious for wearing through the insulation and causing issues.
You are exactly right!!!
I found where a pink wire was rubbing the corner of a bracket. I taped it up reconnected the batteries and tried to start and no go. Checked the 25 amp fuse for #3 ignition and walla it was fried. Up and running now. Thanks again!!!
I found where a pink wire was rubbing the corner of a bracket. I taped it up reconnected the batteries and tried to start and no go. Checked the 25 amp fuse for #3 ignition and walla it was fried. Up and running now. Thanks again!!!
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