HELP: Clock won't hold proper time, randomly changes, is it

Satruday evening I'm at the local car hangout... it's getting late... I start my car to take a younger guy for a ride. Go to start the car and get a click from the starter but no start, turn it off then start it normally.

Clock says it's after 1 AM, "geeze it's getting late" I think. Get back to parking lot turn the car off, then try to restart w/o issue... looked at the connections on the starter and those are fine... one came loose post header work once and the starter wouldn't even click.

After a bit... we decide to go to Starbucks... I pull out my cell and realize it's 11:30, then check my watch and sure enough it's the same.... crap :confused: So I go reset the clock in the car to the proper time.

After leaving the coffee place, started the car and all was fine... drove back down to the beach and stopped by the bar where my gf bartends for a beer... after leaving there no issues.

Didn't drive the car yesterday.... but today I decide go go into the garage and see if the clock is still on "schedule" and truned the key to the on position. The clock read 5:08 when in reality it was 7:50am.... so I'm confused.

Do I have some sort of electrical issue where it's loosing power and resetting the clock? Or is the clock radio malfunctioning and simply not keeping time properly.

I recently had my gauge cluster fail, so I drove around for a few weeks w/o issue w/o gauges until I could get a loaner from Pace This and get my cluster sent to him, repaird, and sent back. I put that back in begining of last week w/o issue, all works well there now... I did disconnect the negative battery terminal while doing that.

Any ideas, or anyone have this issue before?

TIA,
Brian

ttt anyone?

[TomW]

How old is your battery?

[BruceF]

Sounds like a weak battery or bad connection/ground issue. What is the voltage reading on the battery? Are there any codes stored in the DIC?

[c4c5specialist]

HI there,
Yes, I would be leaning toward a solenoid or a connection issue.
Reason your clock reset is that your actually battery power, went below a 9 volt threshhold.
Look very closely at every connection from the battery to the engine and battery to BOTH fuse blocks.
Allthebest, c4c5

Thanks... I'll recheck the connections to the inside fuse block... the one to the fuses in the engine bay is secure and tight.

UPDATE:

Took the battery out and took it over the advanced to see if they'd give me a new one. Because it wasn't leaking they wouldn't... they had to put it through their tester. This took a bit over an hour, the battery passed all tests, and left them w/ a 100% full charge.

W/ the battery out I removed the battery pedestal and the plastic "heat shield" thing and instpected all the connections. The negative terminal ground on the frame rail right by the battery was very very dirty and had lots of crap built up on it. I removed the nut then all 3 wires and cleaned the area w/ electrical parts cleaner and a wire brush. I then cleaned all 3 wires and put it back together.

I checked over the starter as best I could and all the engine gorunds I could (2 front on the frame rails, one on the back of the driver's head, the one on the left side of the block, and the negative terminal on the right side of the block... all is clean and tight.

The actual battery cable hookups still had some surface corrosion on them from when the last battery had leaked... so I cleaned them as best I could w/ a flat head screwdriver, wire bristle brush, and electrical parts cleaner. I then coated each in some di-electric grease and re-installed the battery making sure the terminals were tight and clean.

I re-set the clock, checked at about 12 am before going to bed and then again this AM and the time was correct. The car starts finea nd all electrical systems work.

Hmmm... the battery did go dead a few weeks back after the car sat for almost 2 weeks w/ the cluster out... I'm not sure if having the cluster out and driving it allowed some power draw to stay "on".

Then.. I did a slow charge to where the car would start and drove it... I wonder if it just never got a full charge, and when sitting was loosing charge quickly enough to make the battery drop below that 9 volt threshold.

C5s sure are fun when they get electrical bugs...

I f'n jinxed myself... a few months back I said to a buddy, "I've been rather lucky w/ no electrical issues in this car, only mechanical" Then I jokingly though... shit I just screwed myself. A few weeks after that the gauge cluster failed.... now this.

Hopefully the full charge/test on the battery, cleaning that ground, and installing it securely will do the job.

[TheRobSJ]

A nreal longshot here but I thought I'd throw out...

I had a 2001 Silverado. The radio unit is practically the same one used in C5s. When I bought it I was foolish enough to buy a LoJack with it. They wouldn't tell me where, but it as easy to figure out they installed the LoJack module in the dash behind the radio, and t'd off the power lead to the radio to provide power to it.

Every so often, the radio would lose the clock and presets. I pulled it and checked the connections and found that splice they used for the LoJack actually cut the wire and was causing an intermittant open circuit. After reapiaring the connection, I never had a problem with the radio losing time.

I think it's fixed (knock on wood) tome has stayed proper as of yesteday morning, last night, and this morning. Think is was a combo of a slightly weak battery and undertightened cables.

[ToolGuy]

Be careful of that frame rail ground block, the one with the 10mm nut. If it is not tight enough, it will cause weird things.

I loosened both the drivers side and pass to clean them. Weeks after I was out driving and got a reduced engine power and check engine light in the middle of the street. Limped if to the side, luckily it restarted with full power. The MIL was for the TAC module, loss of communication.

I checked that nut and it turned another 1/4 turn. I did not want to over tighten it in the beginning for fear of snapping it off. Both were rusted on as well and I had to soak them for days before they would even come off. All was fine since I re-checked the nut.