2004 Coupe

2 year old fully charged battery @12.6v

Battery cables tightly secured and clean and free of any corrosion.

Alternator putting out sufficient voltage when car is running @ 14.7v

New CPS

New Fuel pump

New fuel filter

Car idling and suddenly all 12v power cuts out for a split second and the car stalls.
Turn the key off and the car will then immediately start right up.

No "check engine light" and no stored codes.

BAS ESP light of course is on due to the complete 12v battery loss of power.
Turn steering wheel full left to full right and the light resets as usual.
All is fine for a few days and it does the same thing again.

Mystery no start thread says car cranks but won't start.
CPS thread says car will crank but not start until cooled off or a short period of time.

My situation seems to be different than any other I have read here.

Any ideas that have not been discussed here before ??

 

Rudy is in your back yard Gary...it's seems like you are losing electrical feed for a moment. This could be anything in the power line from the battery down to the starter back up to the fuse box....check all connections at this point. Power also goes to the steering column to the key. Anything in that line would cause this ....cause all power to go.

 

Gary, it still could be the RCM giving you the problem. Sometimes it only takes a second for a bad connection to cool and reconnect. Take care of the common problems first before you go chasing something you can't find. I would do that first before going any further.

James

 

sounds like a ground wire check all of them rudy knows where all are located. jim

 

The grounds are mostly brown from what I've seen on my car, pretty easy to find them where the meet the chassis. I'd start by taking them off and cleaning them up with a wire brush.

 

Mystery no start the car has all electric and engine will not crank (turn over).
Surely you have already resoldered the RCM by now anyway.

You say battery terminals are clean. How about the inside of the terminals where they contact the battery posts?

Grounding sounds like a likely problem.

Powertrain control module would be a worst case scenario.

Hope you find it!

 

My point is the main power feed wire from the battery...first place I would look. Also the ground wire is a good point as well. You should trace the main feed to the starter, fuse box, interior fuse box, ignition...this main feed is a hot one, but a ground wire will cause the same symptoms... I just had a wire to the fuse box on the Tahoe cause starting problems. While looking for that connection, I found other connections corroded. Side post terminals were really bad after I took the plastic covers off to inspect, as well as starter terminals...cleaned them all, but the fuse box connection was the problem. Probably started back when I wired in the electric brakes for the car trailer...anyway, certainly sounds electrical, and James may have a good point as well...seems the RCM can cause a lot of problems. Rudy would have the best test equipment for testing voltage...put the meter on, and start wiggling wires...look for a bad connection...good luck...

 

I did talk briefly with Rudy tonight and yes he is fortunately local to me.
I'm sure he will be the one to ultimately find this very intermittent problem.
Being winter in Chi town I'm not driving the car much now anyway.

As far as my RCM it has never been out of the car or touched by anyone.
I got this car with only 17000 miles in 2007.
I spoke to the only owner before me after purchasing the car and he said he never had any issues during his first 3 years with this car.

I now have 75000 miles and other than the CPS and fuel pump this is the only other mechanical issue I have ever experienced.

Additional feedback is welcome.
I just wanted to throw this out to the forum to see what feedback and advice I could get.

 

My guess is that it is not a ground wire as poor grounds do not cure themselves that quickly, possibly ignition switch or something directly after the switch.

Maybe the engine fuse block, splices or under hood fuse block.

Take out the RCM and check for corrosion on pins, not too likely though.


That security air/vacuum pump what ever it's called controls far more than the doors as well.


Certainly not the starter circuit.

 

wiring gremlins are a big pain...just about have to look at everything...to track them down...good luck Gary....I know you will find it, or the Speedriven crew will...I am trying to come up with a date to come up there, probably sometime in Jan...

 

Man oh man, these types of issues are ugly, and an owners worst nightmare.

If it would just fail solid, finding a comfortable fix is so much easier.

Most of my ideas were covered, as I would probably goto a ground run, RCM, or somewhere in the Battery or cabling.

You said it happens at idle, just curious if you ever experienced it at speed when driving...???

Now that would be coyote ugly in my mind...and very dangerious...

 

So far it has only occurred while idling in gear at a stoplight 3 times.
It has never happened while moving/driving
And it occurred once in the garage when I went to start it...no power.
A couple minutes later it started right up.

All along the battery is at least 12.6 volts.

 

Valk,

Tina says that it's the inhumanly cold weather up there!

Move south-it will solve ALL of your problems!

 

Are we talking about a 5 or 6 speed car here?
By all I take it you mean a total power loss, no dash lights etc.

 

Autostick and yes....complete loss of power as if there was no battery in the car.

 

Ha....it was 53 degrees today !!

 

Batteries cause over half the problems with cars, can you try someone else's battery for a while. I think that possibly one of the posts may be loose where it attached to the inner buss bar.
I had a similar problem to you and it came down to a loose, or rather a not tight enough battery cable. But you have checked that and they are OK, are the cable terminals and posts shiny? when lead oxidizes it is a flat grayish color, it looks OK but is in fact insulated.
After that I would check the cables, there have been reports here that they cause problems when corrosion is inside the plastic insulation an not visible.

I suspect the problem lays in the battery or close to the battery, go to the grounds and particularly the power connections close to the battery.

The farther you get from the battery the less likely the chance of a total loss of power.

 

Oddly enough the weather in Chi-town has remained clear so far this winter so I have been using the Crossfire as my daily driver and more than 3 weeks have passed since I started this thread.

I have not experienced this problem at all during this time.
Fingers crossed that it won't happen again but.....

 

Well, Gary: you've done it now.

 

i had a similar problem with my slk32. 3 times so far once at the starting line at the track. car layed down fluid and they held me at the line. shut the car off and it wouldnt start. then it did. twice in my garage.
found the negative cable is bolted to the front inner fender. the bolt was just loose enough to allow a ground loss. always checking it at the battery i never checked it at the other end. tightened it and no more power loss