vetteship

Hi guys, coming from the C6-ZO6 camp and an ex-C5 Vert Owner.
My colleague at work have a 2004-C5, no codes are set (history or current), the memory is not holding the seat/radio/and side view mirror positions, and seat/steering is not going back when you open the door to exit, what could be the problem, any help/suggestions are appreciated ?
Thanks

DefenderC5

GM electronics are finicky. Start with a test on the battery.

EMINENT 1

I've read a lot on this, it could have something to do with the grounds being corroded. If you do a search for seat or memory, you should find a thread about grounding points that need to be cleaned.

I haven't done tried that. I still have this problem. I have possessed side view mirros that hardly ever returns to where I set it. It'll come close, but never spot on. Once in a blue moon it will. Sometimes my seat will go back and sometimes it won't too. I just deal with it. It's f'n aggravating!

Bill Curlee

Battery!!! If its low or going bad, it will cause a LOSS OF MEMORY. Happens when you crank the engine! Battery voltage drops below 9 VDC for just a millisecond or so and thats all it takes! Once the engine starts the battery voltage returns back to normal and what you will normally see are U series DTC's or a loss of memory and sometimes loss of FOB sync.

Been there done that!

Bill C

EMINENT 1

I have switched out my battery with no change and memory not working. My current battery is also a new unit. Still having problems.

ajg1915

Bad seat control module.

vetteship

Just changed the battery to an Optima red top, still no memory and no codes, excpet for chk engine light on, (went off after turning and starting the car 3 times), module was changed at the dealer 2 months ago when codes were set. Very frustrating. I am going to check the ground resistance values at different ground lugs to chasis points and correct if I need to by removing the lugs scraping the paint underneath and re-instaling the the ground lugs.

Bill Curlee

C5 Ground connections are a LOT more complicated that just removing the nut and cleaning the TAB!

Here is where the REAL problem often lies!!!

Remove the connector!



Find the small plastic latches on BOTH sides of the connector:




Release the catches, and pull on the tab for both latches one at a time. Once the end is pulled out, this is what you will see. Mine was GREEN with corrosion! :



Here is the female side of the connector:



Clean the connectors, the ground tab and the ground stud on the chassis.

Bill

vetteship

Thanks bill, thanks for posting and for your help, my weekend just got busy, where is the location of the ground connector

vetteship

Guys, I feel so stupid (and so does my neighbor), after locating the ground wire and upstream connector, we cleaned it pretty darn well, yes it was dirty, but not any more, put everything back and the memory nusense problem persisted. Still NO CODES..., now here'e where the stupid part comes in:
As I was looking at the key fob, I noticed it was key FOB 2, so I asked, where is FOB 1 ?
Oh, the battery is dead so I've been using FOB 2 and that's when the memory trouble started , All sorted out now, installed a new battery in FOB 1 and I was able to explain the difference between the two

hotwheels57

...no reason to feel stupid. It's not as if it hasn't happened to others before...they just weren't men enough to admit it!

jimcork1

Maybe someone can help on this. My 99 C5 seat memory works and the seat will go forward and steering wheel adjust. ON exit the I hear the click and steering wheel moves to exit position but seat does not move. I can move it with the manual power switch. I suspect a relay has failed but is it in the seat control module under the seat or somewhere else? Any help here is appreciated.