How to replace bulb for on-board computer

[hilman]

The light has gone out on my 993 on-board computer (the one at the bottom of the tachometer).

Any one out there replace one before?

Need some instructions.

Thanks,

Jeff

[Waffen]

The light has gone out on my 993 on-board computer (the one at the bottom of the tachometer).

Any one out there replace one before?

Need some instructions.

Thanks,

Jeff

I have the same problem on my 993. I got a quote on this and it was over $500, and this was while the dash was already dismantled to replace some other lights. The technician said it was a royal pain in the *** and if he was going to charge me this much for it I figured I wasn't going to take it on myself.

Seems like a pretty major screw up on the design side to make this such a pain, but whatever. I'm learning to squint.. ;-)

[mgianzero]

Guys,

I sold my 1996 Targa that had an OBC since it was a tip. However, before I sold it, I changed out the bulb for the OBC. Initially there was just a ghost of the numbers. When I change the bulb, the display changed back to its usual orange hue.

This was a simple change. But since I no longer own a 991 with an OBC I cannot tell you step-by-step how I did it. All I remember is that it used a standard instrument bulb (there are only two types used on the 993). I think it required a few screws to be removed from behind the tach to get to it.

Send me an email if you still need help. It's a simple DIY. It does require you to removed the steering wheel to do this. But I know an easy way to do this.

Hope this helps -

Marc

The light has gone out on my 993 on-board computer (the one at the bottom of the tachometer).

Any one out there replace one before?

Need some instructions.

Thanks,

Jeff

I have the same problem on my 993. I got a quote on this and it was over $500, and this was while the dash was already dismantled to replace some other lights. The technician said it was a royal pain in the *** and if he was going to charge me this much for it I figured I wasn't going to take it on myself.

Seems like a pretty major screw up on the design side to make this such a pain, but whatever. I'm learning to squint.. ;-)

[rozinante]

Try Googling Tore Bergville. His websit has detailed instructions for this and other electronic repairs geared to the DIY. I have never tried any of his procedures but he sounds very knowledgeable. I would like to know if it works. Rozinante

[BigBitz]

I tried Googling Tore Bergville. No such luck.

[EleCTriCT]

Use a plastic trim tool and simply pry the tach right out of the dash.. you have to be careful not to damage the leather.

The gauges have a ribbed rubber seal that holds them in place... thats all.. again be caurefull of the leather and / or slipping damaging the gauge.....

Then your on your own because i cant remember which bulbs etc but should be self explanitory once you get it out..

Once done press back in with the seal on the gauge first.. some silicon spray may aide in the install.... also watch that it goes in level... Unless you want that tuner look where the redline is at the top :thumbup:

cheers

also.. http://www.renntech.org/forums/topic/41003-access-to-rear-of-gauge-cluster-to-replace-bulbs/page__fromsearch__1

Edited March 12, 2012 by EleCTriCT

[paultwinturbo]

I tried to remove the OBD tach without removong the steering wheel and air bag as called for in the service manual. It doesn't work. All you do is damage the bezel. Also, while replacing the light can fix the OBD backlight problem, if it doesn't, you'll have to go the $500 route. Once you remove the two long screws that hold the back on the tack and the screws holding the large circuit board, you can easily remove the blue light and replace it. You want the 0.9W, 964 641 920 00. The instrament lights are 1.5W 999 631 027 90.