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Dtc C0300

Lee Robertshaw

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Lee Robertshaw New Member

Lee Robertshaw

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I was getting a DTC C0300 code in my 2005 Trailblazer. All the 4 wd positions worked and the code light would shut out every time you started the truck but would reappear at some point. I took it to my dealer who said It was either a bad rear propellar shaft sensor or the TCCM needed to be reflashed. I wasn't ready to believe that the software in the TCCM magically went bad so I left and said I would think about it. My girl friend came over and told me she was using my Blazer while I was out of town and that the service 4WD light came on. She gave me the bill for the work and the dealer had repaired the wiring harness to the speed sensors for both drive shafts. Not bad 235.00 except she said it was worse so she parked the Trailblazer and took my car.

 

Off to the dealer I go and by chance saw the service manager. Told him whar was happening and he brought out a scanner and went for a ride with me. Up popped the code as we drove around. He was watching the propeller shaft speed for both the front and rear driveshafts and something called the slip speed. We went back to the dealership he said he new what was wrong. He himself put the Blazer on the hoist and had it back on the ground in about 2 minutes. He said Quote my apologies the technician plugged the front and rear propeller shaft sensors in backwards after the repair. Thanked me for bringing it back and assured me I was good to go. That was 5 days ago and all appears to be well. Now I just have to get my car back from my girlfriend.

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