polecat702

I've been told by the owner of a Porsche repair shop here in Vegas that the 928 dash should lite up when the key is turned to the start or run position. The only lite that comes on is the antilock feature. He said that there are many more that should light up. Is this something that I should let a pro handel or something that I may be able to do myself? Electrical is not my strong suit. My shark is an 87 S4 Auto, the PO replaced the factory radio with a Pioneer, It has so many features that I haven't been able to tackel all the programing. Any help would be greatly appriciated. Thanks Joe.

Hold On

He is correct. If your car has the non-digital dash. It should light up like a christmas tree when the key is turned to run. The warning lights for high temp, low fuel, low oil pressure, low voltage and numerous other sensor lights for things like brake pads,low coolant, etc. This indicates they are functioning. When car is started they all go out except those connected to park brake and stoplights if yours is the same as my 83. Why yours does nothing is beyond me guessing.

Alan

I'd check out the alternator connections. Have you been having any charging issues?

The alternator exciter line that goes from an ignition supply -> the chargelight in the dash -> alternator is important in "bulb test" mode.

There is actually a resistor in parallel to the bulb too.

When the ignition is turned on the charge light should be on (obviously it isn't) this is not part of the bulb test mode - its quite independant. The other lights all come on in bulb test mode because this one is on (strictly because it has ~0v on the non ignition side of the bulb). When the car is started and the alternator starts to generate this point goes to ~13v and so does the ignition supply - the charge light bulb goes out and thats what causes bulb test to end....

If that connection ot the alternator is broken:

1) The charge light won't come on

2) Bulb test won't start becuuse the far side of the bulb is already at 12v

Check the alternator connections - even if it is charging it probably isn't connected correctly.

Find the small connection to the alternator - remove it then ground that wire and see if the charge light comes on when you turn the ignition on if it does (and wont with it connected to the alternator) you have an alternator problem. If the charge light never came on you have a wiring problem.

Alan

polecat702

Thanks guys, All the gauges work, tach, oil pressure, coolent temp, battery, when I turn the key to the on position, the only dash lights that come on are the anti-lock, and the red lite at the bottom of the charging gauge. when I start the car I get readings from all the gauges. The alt/battery is just under 14 volts, oil pressure at 5, tach at around 900 rpm. Alan my son is a journeyman master electrician, and a licienced comercial contractor. he told me by the way you write your posts, he's sure you are an electrical engineer. But when it comes to this car he is scared of making a mistake, and causing more harm than good. one thing that he did find was that it looks like something shorted out in the relay/fuse panel. There is some black residue around the fuse connections. My son thinks that they shorted some of the circuts out when the new radio was installed. I've got the wiring diagrams on disk, we're going to print them and check out the Alt wiring to make sure it's wired per the prints. Thanks for all the help, Joe

BBX

There is a fuse in the fuse panel, that say something like interior lights? I can't remember, but it was something I wouldn't think to check that did it for mine. I would check all the fuses, if you haven't already.

BBX

Do you have the white and green plastic cards with the fuse title and location list?

polecat702

No Blythe, I Don't. I have all the srevice manuals on a disk, and can print whatever I need from them. I thought that is all I would need. The green & white cards is something new to me. I've only owned this car for 7 months. I'am learning, but I know I 've a long way to go. This 928 can't be any worse than my Pantera, that thing has parts from Germany, Italy, America, and Ford. It's a real morphadite. At least the shark has all German parts. Thanks, Joe

knussear

I had a similar issue with my 82, also in las vegas. I found out the central warning computer was un-plugged by the previous owner, Check the plugs on the unit under the left foot rest.

polecat702

My car has been sitting for a a few months, just haven't had time to work on it. I need to replace the master cylinder, and pads. I'll get in the wiring also. Knussear PM me, would like to meet another shark owner.

Brett Jenkins

i think there is a module under the dead pedal for this. If there was an issue that the PO didn't want to address, unplugging the warning module would do away with those annoying warning lights.

Maleficio

I replaced my Central Warning unit under the dead pedal and now my dash lights up like the afore-mentioned Christmas tree.

Now I've three new problems to fix: tail lamp out (side one, guess I'll have to pull the tire to get to it), brake pressure (failed circuit, guess I'll have to change out the pressure switches) and coolant. I topped up the coolant, though it wasn't low. I figure the level sensor is going bad.

I'm just happy my fault feedback system is working properly, I don't care how many problems pop up.

SteveG

At "928gt.com" you can print out those "cards" which are relay and fuse diagrams. Look for your MY on the lower left of the home pg. I would do two sets and laminate one and keep it in the car. There should be a sleeve attached to the wooden foot plate under the passenger carpet for it to slip into.

tveltman

It's possible that you just have a ****load of burned-out bulbs. If so, it might be a decent opportunity to upgrade to LED. There are posts floating around about parts/sources, etc. I would do it if I didn't already have my hands full. In your position, though, definitely.