Started having problems while out of town. Car died while driving on highway, then when trying to start it, the starter went out (I could hear it spin) It was 2 times prior to that on same trip that after turning key to start nothing happened, but would turn over the second time trying. So this was the third time with issues trying to start car. Only place I could tow it to was a chevy dealer in a small town. Told them it was the starter and if they could change it. They were able to put an after market starter from Napa. (GM starter would take sometime the following day and I could not wait) After paying an arm, leg and a left nut as well as a cracked splitter and A/C now not working, I drove off the lot and less than a mile away car died. Everything on but motor was not running. I put it in neutral while rolling and it started up but immediately died and did not stay running. I rolled off the road and starter sounded like it was only cranked halfway because it immediately stopped cranking. I would turn the key and hold it and still just start to crank then stop then another half crank and stop. Checked codes and got the P1626 and figured it was the battery was not really charged after trying to start it before towing it to the dealer. So I connected a portable jump starter I carry in car to give the battery some juice. After about 10 min of trying to start it intermittently, it finally turned over and started. Drove to hotel I got for the day while waiting for the dealer to install starter and waited about 2 hours before getting back on road. Car started right up let it run for a bit and had no problem getting home. The next day started right up.
That same day I drove to fill up the tank and to grocery store started with no problem but on the way home car just died again. I and could not get car to start called someone to try to give me a jump with their car and nothing. But while trying to start it I got the pull key out for 10 seconds warning a few times then I get the column lock warning on the DIC. Immediately gave up called a tow truck to get me home. I do not remember the exact codes but I do remember they were the lock column codes and the P1626 along with the U1064 the 2100's regarding the TPM. I would clear them and try to start it and would get in random order the codes about the BCM and column lock. It would still not start the next day, then I read about the LMC5 and ordered it express delivery. Got it in 2 days installed it and started right up. Drove to a friend's house that night with no problems so I take it to work the next day and on way back to my office from lunch car just dies. I check for codes and only one was P1626 and would not start. So once again got it towed home. Cleared codes and tried a few times to start didn't start and no codes even after again charging battery till is showed fully charged was not really dead though. So I hooked up my laptop that has a program like a scanner that reads what is going on. nothing in code history but I did notice that that the setting was showing active for VTD fuel disengagement and another thing or two under the same VTD section. I am thinking either the BCM is going out or maybe the ignition is not getting the right password or code from the ignition switch I am sure it is in the VTD mode. Will that also affect the starter, cause it sounds like it isn't allowing it to turn cause it stops halfway through the crank. Could a bad ignition switch or bad BCM have this effect? I think the other codes about the 2100's the U1064 are getting thrown in after I keep cranking on it.

Any suggestions or insight would be greatly appreciated. It's my daily driver here in Phoenix and I cannot chance being stranded on side of the road again in this heat and riding my motorcycle right now isn't much better. My car is a 98 base model, automatic with bolt on mods. Haven't had any issues with it until now and hopefully will not be too much of an issue to keep it going

 

I think it may just be a bad ignition switch...I replaced mine last year so they do go bad !!...mine car didn’t die on the road but the only time it didn’t start I then cycled the key a bunch of times and saw that the DIC voltage was only 8 volts or so...I knew I had a big voltage drop across that ignition switch...got myself an AC Delco switch from Rock Auto and never had a problem since !!...does your security light go out when you turn the key to on after a few seconds ??

 

Thank you for the input. Yes the security light stops flashing after the key is turned.. the battery us a week old. Had to replace it after a year, but was still under warranty. I even took it back for them to test just incase it was a bad one. But checked out fine. I will see if I can check on the ignition see if there is a way to determine if that is the problem with out throwing parts at it.

 

I’d try another key and it really helps to have a scan tool where you can look at VTD data through the BCM !!

 

I did try the spare key and same thing no changes

 

One time I had an issue with the car not starting. I sprayed some electrical contact cleaner (CRC Mass Air Flow Sensor Cleaner) into the key slot and have not had any further problems in 3 years. I do the spray routine along with cleaning my keys several times a year.

 

P1626 indicates the PCM didn't receive a state of health message from the theft deterrent system. There could be several issues. Either the Class 2 serial data circuit has a problem or the PCM does. U1064 also indicates a class 2 serial data circuit issue with the BCM not communicating a state of health message. Your issue could be the voltage level, igition switch, the class 2 serial data circuit or the PCM. If you have a known good battery and solid battery cable connections at the battery and at the battery ground point along with a solid battery voltage connection at the starter solenoid you should maybe look at what is happening on the class 2 circuit.

I know from personal experience the steering wheel lock circuit can get logically out of sync when a car is jump started and prevent moving of the car. With P1626 and the U1064 codes being your main codes without any other issues I suspect the problem is in the class 2 circuit.

Bill

 

Thanks so much Bill. Yes, brand new battery and charged, new starter but i will look at the line to it from battery. Ground should be hood to chassis as i recently did the big three. But will recheck and maybe check all other ground connections. I will start looking into the class 2 circuit as I am not too familiar with it but did see that vome up in my researching. Thanks again, now I have another angle I can check on thats different than what I've been looking at.

 

Thank you rrwirsi, I will try that as well. Would be great if that was it. But I have found that, for things that should be quick and simple for others, Mine is always 3 times worse. If everyone just needs a bolt tighten for a fix. Mine would be the one in 100k that a bolt was not used. Mine would be welded...on the opposite side lol.🤪

 

Another C5 horror story - scares me!

 

I have a 2000 convertible that did the same exact thing. Sometimes I would have to try twice before the 3rd time cranked the engine. Also started getting the infamous "wait 10 seconds and try again" message. I've always used 1 key only, the other kept for a spare. With over 100,000 miles on it now, someone here suggested I try the other key, so I did. Presto-That was it. Apparently the chip on the key itself went bad, or was somehow damaged, because now I just twist it, and once is all it takes.

 

I would hedge my bets on the ignition switch, I helped a friend with his C5, same thing the starter would start to crank and then quit.

 

There is no chip in the key , only a resistor with one of these values shown in the table below. The resistance is read by these sliprings and the resistanse value create a voltage drop read by the BCM . This voltage can be seen in the BCM by a Tech2 or similare scanner as Passkey Resistor Value

 

It could be that part that was posted in the previous post, but it can also be pitted and burnt contacts in the contact switch block that is attached to the key cylinder as well.