# Safety Mode - Can't Get OBD Codes



## SpikeyD (Jul 31, 2012)

Hello folks,

I just got my '06 GTO on Thursday, and I love everything about it. Everything, that is, except for this problem. Several times, the engine has felt like it "missed" and stalled or "tried" to stall. The whole electrical system cycles each time it happens, and if it doesn't stall completely, it happens several times in a row. It has happened when idling or when in gear doing 60, right after starting up or after an hour of driving, etc. I took it to my mech and they said the OBD history was incomplete, as if it had been cleared within the last couple days. They said to drive it a few more days and bring it back once it had a history.

Last night when it happened it went into "Safety Mode" and gave me various warnings about the ABS failing, the airbags failing. I stopped, waited 10 minutes, and restarted the car and it ran 100% fine, only the CEL was on. This morning, I bring it back to the mech, only no CEL, and when they looked at it they said it looked like the OBD history was cleared again.

Has anyone seen this problem? I know there is a common issue with pedal sensors in the '05s that causes "Safety Mode," but I don't see that bulletin for the '06, and that wouldn't explain the cleared OBD. Would a bad ECU explain the problems with resetting the history AND the safety mode/engine missing issue? Any other ideas - sensors, harnesses, gas cap, ???

Thanks in advance for your help.


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## ZEIKE524 (Dec 28, 2010)

Check the BCM wiring harness. It's behind the glovebox. Do a quick search on here and you will find anything you need to know/check.


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## SpikeyD (Jul 31, 2012)

Thanks very much ZEIKE. Sounded like a strong possibility to me, so I gave it a shot. No sign of chafing of the BCM harness. While I had the glove box out, I bravely jiggled the BCM harness and every other harness/connector I could reach, hoping to reproduce the problem, but no dice. Doesn't prove anything, but worth a shot. Even if I did break that little plastic clip that holds the glove box to the little post in the back right. 

Any other ideas or similar problems anyone is aware of?? TIA


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## svede1212 (Nov 1, 2005)

You definitely have an electrical gremlin and one I'd wager the previous owner couldn't solve. Does the car have any mods?


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## SpikeyD (Jul 31, 2012)

svede1212 said:


> You definitely have an electrical gremlin and one I'd wager the previous owner couldn't solve. Does the car have any mods?


It looks that way Svede. No mods as far as I can tell - it looks bone stock under the hood.


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## ZEIKE524 (Dec 28, 2010)

Well hell those gremlins can be a real pain in the rear end. Good luck. Keep us posted on what you find.


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## SpikeyD (Jul 31, 2012)

Will do Zeike - in fact, I have an update that may help piece it together. I checked the Carfax and discovered that, shortly before it was sold by the previous owner, it was serviced twice. I called that shop and they told me the first time they replaced the BCM, and when the owner brought it back, they were stumped and didn't do anything - must be when the owner decided it was time to offload it. (Thanks, bud.) The good news is, it rules out the BCM itself. Maybe it's still a bad harness, even if there's no chafing. I'm going to drive it for a few more days and see if I can get any trouble codes to come up - otherwise I'm going to be stuck hoping my mechanic can find something that the other guy's didn't.


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## SpikeyD (Jul 31, 2012)

Alright folks, it happened again tonight, and this time I had the my OBD reader hooked up. While it was in "Safety Mode" I got P2101, P0803, P2101 (again). A quick search tells me P2101 is for safety mode (well, duh) and P0803 is for the skip-shift solenoid. Now I had noticed that skip-shift wasn't working when I test drove the car, so I assumed a previous owner had disabled it.

But here is my question - would a skip-shift failure ever cause the symptoms I've been having (stalls at idle, all electrical systems power cycling, OBD reset, safety mode, ABS/airbag faults)?? It seems unlikely to me, but these are the only codes that the engine gave me. Oh, and after I turned the car off and back on again, those codes were gone and the OBD tests were reset to "not ready."

Anybody have any other tips or thoughts? Thanks again!


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## amdoverclocker (Dec 21, 2010)

I had a similar problem with mine and it turned out to be the battery terminals. Have you checked those to make sure they are tight and there is not corrosion around them? Just a thought...


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## SpikeyD (Jul 31, 2012)

Update - I brought the car to a different mechanic (that the dealer recommended). They talked to GM, who told them that they had seen similar problems caused by the ignition switch - they even have a new part #. The mechanic put in a new ignition switch and I picked it up almost two weeks ago. After I picked it up, I drove it daily and put ~1000 miles on it without the problem reoccurring. Before that, I had never gone more than 24-36 hours without seeing it happen.

So I was pretty confident they had found the problem, when on Tuesday, it happened again - twice within about 15 minutes. No safety mode, but I got ABS and Airbag fault warnings. After that, and now three days and several hundred miles later, I haven't had the problem come back.

So it is still possible that it was the ignition switch and there is another latent issue, or it could be that whatever they did when they replaced the ignition switch helped but didn't entirely fix the problem. One other thing - I noticed my first time driving in the country at night, when I turn the hi-beams on, my receiver turns off and then starts back up, like a brown out when the new load (hi-beams) is first applied. Possibly unrelated, but I figure it means the battery is on its way out. I'm going to try replacing it. 

amdoverclocker, I checked the terminals and didn't see any corrosion, but it may still somehow be a battery connection. We'll see what happens when I put in a new battery.


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## jpalamar (Jul 22, 2008)

Have you checked the BCM wireharness in the dash? They are known for rubbing and exposing wires over time. It can case some crazy things to happen.

http://www.gtoforum.com/f3/bcm-wiring-harness-chafing-28977/#post314603


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## SpikeyD (Jul 31, 2012)

Thanks jpalamar. Already checked that on zeike's suggestion, but there was no sign of any chaffing. I protected the harness just in case, but at the time it continued to have the problem.

It's been almost another week and several hundred miles trouble free, so I think it was probably the ignition switch but there is still a connection somewhere that is not quite right.


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## SpikeyD (Jul 31, 2012)

UPDATE - I still don't have a 100% sure answer on this, but it may be a long time before I do so I thought I should circle back in case anyone else has this problem some day.

Before trying to make any other repairs after the ignition switch was replaced, I borrowed a friend's ScanGauge II and set it to show me the alternator voltage while I'm driving. Most of the time, the alternator is nice and steady in the mid-13V range; however, once in a while, it will start jumping around in the range of 12-14V, and it will slowly get worse until it fluctuates between <10 to >15V. Then, and not until then, do the electrical problems start. So I am pretty sure the voltage regulator is shot in the alternator. The oddity is that, not only does this only happen once every few weeks (instead of every few drive cycles like before the ignition switch was replaced), but all I have to do is turn the car off and back on and it goes back to normal every time. I don't even need to let it sit - I can literally do it while coasting between traffic lights if I notice the voltage acting up.

Eventually I will replace the alternator and I will know for sure, but for the time being I am perfectly fine (it's cheaper) with just leaving the ScanGauge hooked up all the time and restarting the car if I notice I am about to have a problem.

Thanks to all you guys/gals for the help.


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## ppxstnr (Mar 7, 2012)

Not sure if our cars have an actual regulator. I was thinking the ecu or bcm controlled this. Also if cags is disabled, I would have a stock tune flashed back in the ecu. But based on everything you posted thus far a voltage drop is probably the issue. Same with the corroded loose battery. Keep us posted.


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