SMehder

Hi, I'm a new 993 owner, but not new to the Porsche world. The 993 shares the garage with my older 912... which is quite simple to work on.

That is the problem. My on-board computer works great, except for the light. It appears to be burned out. (Assume it does not have a seperate fuse). I have done a search and find one thread that indicates to replace the light requires removing the steering wheel, and air bag. Another suggest that it is easy to push the tach out from the back with a broom handle (don't know what that Porsche number is). Another thread suggest that the tach can be pried out from the front. The Porsche 993 Essential Companion book indicates it is very easy to replace the light. I am confused.

How easy is it to fix? Is there a seperate fuse? Can the tach be removed without removing the steering wheel and air bag?

Thanks in advance.

Barney1

In the rear of the gauge there is a bulb for that display. It is the same as all the other dash bulbs. The wheel,airbag and plastic covers on the collum need to be removed. A trick, when pulling the airbag out, have a friend hold it to leave it pluged in while removing the steering wheel.

SMehder

So there is no seperate fuse? I guess this explains why the PO never fixed it. I don't think I want to go through thought of removing the steering wheel and working with the airbag.

I guess the only other option, assuming no seperate fuse, is to take it to the dealer.

Stealth 993

NO, there is no separate fuse for the OBC light. It is the same small light used on the rest of the dash gauges. They are not cheap, I want to say like a few dollars each. I think it takes 2 off the top of my head, it's been a year since I did mine.

You can remove the tach with out remove the steering wheel, it's a tight fit & you got to work it out, slowly. I removed the speedo, then pushed the tach from behind. Then just wiggle it out. The whole process takes about 20min.

SMehder

Thanks Stealth 993,

I knew there must have been an easier way to remove the tach. Regarding the price of the bulbs, any item of "a couple of dollars" is cheap for Porsche.

Barney1

IMO, If you don't take at least the plastic off of the collum you will scratch it. You might want to put painters tape on the plastic if you dont remove it.

SMehder

Thanks, Barney1, the tape to protect the column seems alot more feasible than the removal of the steering wheel.

Texas993

FYI, changing the bulb did not fix my dim OBC. It can be sent to Hollywood Speedometer and repaired for a cost of $500+. At that price, I am ok with dim.

Stealth 993

There are 3 separate wattages you can put in there. When i first went to the dealer they only had I think .9w & the stock is .6w or something like it. My OBC was WAY to bright, & I ended up putting the .6w in later.

David in LA

Is it possible to replace the light bulb with a brighter LED bulb?

ToreB

I'd put my money on a faulty transistor inside the rev counter. It's a very common fault on 964 and 993. Changing the transistor is easy for a guy with some soldering experience, I've done it several times for Porsche buddies. Here's a link to a How-to:
https://rennlist.com/forums/993-foru...-repair-2.html
Regards, Tore

steerpike

Having got the tacho out, which I managed and then tried pushing the dial with the OBC display on it past the steering wheel mounting, which holds the indicator controls and is static even after turning the steering wheel to any and all angles it won't go past.
Even took off the indicator mounting,still stuck.

This is a 1997 cab 2 by the way

I am hoping to get at the back of the OBC to get bulbs out tomorrow, through the hole for the tacho, but I dunno.

If any one have any other advise I would be most grateful.

Many thanks. John.

JM993

The steering wheel must come off to remove an OBC tach. The OBC tach is larger (deeper) than the non-OBC tach.

Cheers,
Joe

ToreB

I've taken out several tachometers, all with defective OBC light. (maybe five or seven) None required taking the steering wheel off.
Patience and some soap water from a spray bottle helps a lot.
Cheers,
Tore

JM993

Soap and water? Really? Why not use WD40?

To the OP, removing the steering wheel is easy. If I were you, this is how I'd do it.