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I just got my 1988 C4 convertible back from the Upholstery shop. They told me that the battery died and they had to recharge it. Whenever I turned it on to drive it home, I noticed the dash was dimly lit, some parts not lit at all and not displaying my rpms, speed etc. Also when I was driving back it would randomly die while driving and it wouldn't shift into overdrive (it has the 4+3 trans). Any ideas?

 

- your pics don't look good. was the instrument cluster working OK before the upholstery shop visit? so, you take it to the shop, they charge the battery, and now you have this (instrument panel) - suspicious to say the least, but proving them at fault is going to be the problem. not sure what they could have done -- some sort of reverse polarity on the charging procedure, or ??? - who knows? since they were doing interior work, who knows what they could have done. maybe they disconnected one of the many grounds in or around the dash. you might try and check the electrical connections at the IP, but not sure what you can do at this point. you may just have to pull the IP and send it to Bryan at batee for diagnosis. just looking at the pics and seeing dead segments on the display tells me you may have issues at the integrated circuit (IC) level on the circuit board(s) or the LCD panels themselves. IMO, batee may be your only option at this point. as for the engine randomly die thing, and the 4+3 thing, no idea, but many electrical issues with corvettes are associated with grounds. good luck with this one - .

edit - get your FSM, and look at where the IP picks up it's ground, double check that. it just may be a ground issue. electrons are funny things, especially with integrated circuits and semi-conductors. if they don't have a ground path , they will seek out another....

double check any wiring associated with the ignition system and 4+3, especially under the shift console bezel. it might have something to do with it - ??? sounds likes the upholstery shop may have been monkeying around with the interior wiring.

 

This happened to me recently. Turns out my alternator was dying. Replaced it and now all is good.

 

Sounds like the main ground on the driver side. Check this article for location.
https://www.corvetteforum.com/forums...on-a-88-a.html

 

A Picture is shown here. It is under the carpet on the frame rail so very possible they disturbed it.

 

Thank you so much for the helpful response. I'm in a bit of a predicament with proving the shop at fault because I'm deploying overseas in less than two days. However; I called the shop and they said the only thing they did is recharge the battery using a battery charging machine. I'm guessing they sent way too much power through the vehicle. The instrument panel worked completely fine beforehand and same with the 4+3.

I first signeds with getting a new battery, as the old one was completely fried, and this at least helped with the stalling out issue. The shop said they didn't touch any other wires or electrical besides the battery because it's a plastic window they didn't need to mess with the wires.

[EDIT]
Just kidding, it's still dying out and giving me a service engine soon light.

 

Have the alternator tested.

 

When they recharged the battery, did they do it with the cables hooked up and did they do a fast or slow charge rate?

Personally I never charge a battery with it hooked up to the vehicle. There's also the chance they arced it if it was plugged in while hooking it up, if they touched to ground or even reversed the cables on the battery. Too many possible issues there.

I guess the first thing would be to find out if it's fully charged or not. Some of those symptoms listed might relate to the battery being down and don't expect the alternator to charge up a rundown battery very fast.
All the other suggestions are definitely worth checking.

Thank you for your service. You don't say where the car is but maybe someone in the area could help out while you're overseas. Just a thought.

 

I really appreciate the comment. The first thing I did was in fact buy a brand new battery. Didn't really solve anything besides being able to cross one possible problem off the list.

It would be awesome if someone could help but I'm putting her in storage tomorrow. 57k original miles, it's a shame this happened to such a beautiful Vette.

 

Mine did that a couple of times. Same circumstances. (I didn't start it often enough and the battery died.)

Disconnect your battery, wait a few minutes, and hook it back up.

 

What you have is a Digital Dash with "Age" Issues.
That piece of equipment was built when it was "High Tech" but some of the components have a lifetime of half their true age.

There is ONE man who truly "knows" the Digital Dash and its problems. You need to speak with Bryan Thompson at BATEE.COM.
Bryan stocks many of the parts and will help you help yourself if you feel you are capable of soldering PC Board Components and de-soldering them as well. I did it myself but then decided it would have been better to send it to Bryan...

Before you touch that car anymore you should speak with him and show him your pictures.

This is where you will find him :http://batee.com/

I see you are storing your car. That is can be frequently more damaging the car if not done correctly. I have 2 Corvettes, a 1968 427 4 Speed Convertible and a 1988 L98, with automatic Coupe. I would rather drive them and enjoy them for what they were designed to do. I put my 1988 aside for a few years and it took more than a year to "Re-awaken" it. Driving it keeps it current and flexible. Park it and everything corrodes.
Having a Convertible and a Coupe has been nice as I choose which I am forced to endure.

I wish you the very Best with what you do with your car. Just remember Bryan when you want that Dash to work 100%

I am just another very Happy, Satisfied Customer of Bryan's.

 

Looks to me like the dash is acting 'funny' due to low voltage. Get the alternator and battery tested and replace if necessary. I would bet that will solve it... let us know what happens.

 

Nicolas,

I had a very similar problem.

The electronics in the C4 era weren't as tolerance to current spikes etc , as today's cars and trucks.

I had my C4 Convertible is a friends shop in he summer of 2000, we were doing some interior replacements, seat cushions, door seals etc, nothing to do with electrical. The interior lights were left on over the weekend and a few days into the following week., and the battery was especially Dead. So my friend placed a high current Fast battery charger on the battery while it was still connected.

History,, A few months earlier had installed new drive-train,, a ZZ4 GM crate engine, new 4+3 trans, rebuild the Dana 44. We did replaced several electrical pig-tails and we checked all the ground connections. I'm an Electronic Engineer, and picky. I still has this C4, love this car.

So the shop needed to move my C4 ASAP outside for the day while I was at work. The battery was not fully charged so the engine would not crank over fast enough along with the low voltage to the ignition system, would not start. They tried several times.

So they pushed her outside and left the charger on at a lower setting.

At the end of the day, they started my C4 and moved it back inside, The Instrument panel was complexity DEAD. I sent it off for a repair and for a few hundred $$ , the Instrument panel was repaired.


I spoke with the Tech at the repair company and he said, a current Spike, nothing new. Don't happen often, but this is not an isolated repair for the circumstances.

I have an extra complete working C4 instrument panel, think it's a '88 or '89. I'll need to verify the year.

IF your Instrument panel is FRIED, Send me a PM and since your active Duty and if it's the correct replacement,

I'll ship it to you, FREE, Since your active duty.

My Family, every man serves ! Even my Aunt was a Marine Officer. So I fully understand.

Serve Proudly.

Capt. Mike
U.S. Veteran
Oregon