I like a little help on this. I have a 2003 Chevy Blazer with 46,250 miles on it. At times, I will go start it and nothing will happen. I try to put it in start mood and nothing will happen. It will do the normal turn off the radio and other lights, but it appears something is blocking the starter from functioning. If I wait a little bit, it will start. This problem seems to be happening more. And it seems I have to wait a couple of minutes before it will start. This problem is tempormentallish and if i take it to a garage, the mechenic won't be able to dianostic because it will usually work for him. HAve anybody had this problem. Like to have some insight.

 

Does the engine turn over and rev up, but then shuts off? And does your security light flash when it does this?

And ya gotta love the good ol 'could not replicate' [:@]

 

No, pretty much the security system, I/we determined not to be the problem. I took it for a dianostic at my garage. It did show that there was a lost of communication with the transmission and the ABS. He said that is something to go on. Sometime he also said Chevy has can have a bad grounding. It also showed a heater core of an O2 sensor is bad so that will be replaced and they will check more indepth on the starting problem. Anybody that had a simalar problem I welcome some advice.

 

You can get a heater circuit malfunction code from a bad ground as well. I would start by cleaning all of the grounding points. The most difficult one is on the back of the passenger head. Just so happens to be the one that causes a lot of problems too.

 

Well, today, my Blazer came back from the garage. They could not find anything. Then when I left the garage, my check engine soon light came on again. Not very happy. However, I had no problem starting the vehicle since last Wednesday evening(3/13). Does anybody know, do GM dealers have access to codes that Independent garages don't? I think its dumb for these dianostics to tell you that there was a communication loss but not tell you what the problem was. If anybody has insight on this, replies are welcome.

 

It all depends on how elaborate of a code reader the shop has. Many cheap code readers cannot read anything but generic and some manufacturer specific powertrain codes (Pxxxx), but do not include the chassis (Cxxxx), body (Bxxxx), or other sub-system codes.

Without the specific code you were getting, I cannot recommend a direction for proper diagnosis of your problem.

 

Ok, I talked to the garage mechanic today, and this is what I learned. The check engine light dose not appear to be a new problem, as I learned that they didn't put a new O2 sensor in. He showed me the Pxxxx code that are common. That had to do with the O2 sensor. Then there was too other codes. (U1026 and U1041). The U codes he mentioned is a body code. Does that sound right? But these 2 codes are whats they can't figure out. The diagnosis code reader comes from Snap-on and I suppose thats not consider cheap. But it doesn't tell the exact problem with the U codes. So what do anyone believe should be my next step?

 

One last thing, I did go a whole week without the starting problem. But that doesn't really tell me anything yet. But better then having it happen to me twice last week.

 

Well, what was the Pxxxx code?

U1xxx (Loss of Communication) Explained
U1026 == Loss of communication with the TCCM (transfer case control module)
U1041 == Loss of communication with the EBCM (electronic brake control module)

Neither of these should cause a no start condition...

 

I got my code today. It is P0155.
What would cause a loss in communication? Is that something that I should be concerned about? Next month I have an emissions test due on the Blazer, and I can't pass it with the Check Engine soon light on. So if the engine has no problem starting and we have nothing to go on, i will concentrate on passing the emission test.