Later 986 instrument upgrade

[Derventium]

I've read with interest the posts for upgrading earlier model 986 instrument clusters (with the black, white and blue connectors). The programming information (for using the GQ-4X eeprom programmer) refers to the 93C56B 2k eeproms and is quite thorough. Unfortunately, as I have the later model car (green, blue and grey connectors) using the 93LC86 16k eeprom so the information is useful only as a guide.

I've managed to get my hands on a later 996 dot matrix dashboard with the extra dials so was wondering if anyone out there has any information as to how to re-program the later chip and where the relevant data is stored - when I read the later chip it's got a LOT more data stored! The data I'm looking to verify or change is:

1. VIN
2. Mileage (lines 300/310 and 500/510 but I can't seem to see the later address lines)
3. Speedo calibration (new clocks are 200mph not 180mph)
4. Fuel tank calibration (not sure if the new clocks were from a C2 or a C4)
5. Convertible / Coupe data
6. Anything else I may have missed!

The VIN is pretty obvious but I'd like to keep the original vehicle mileage so that it's service history doesn't show the vehicle as being 'clocked'. My car is an early 2001 pre MOST model. I did download a .pdf from Rennlist but it only contained basic information about VIN and mileage. BTW, when I connect the new dash in the car it appears to work, albeit with 30k less miles!

Hopefully, someone out there can help?

[Chuck W.]

I may be wrong.... But.... I believe you are doing more than needs to be done. I changed from the stock Boxster cluster on my 2001 Boxster S to a 2003 996 cluster. I also have the green, blue and grey connector on both my Cluster and the 996 donor. The only change I made to the 996 cluster was to send it in to ODO-PRO.COM - Odo-Pro.com - The Digital Odometer Professionals and have the odometer changed to my Boxster's for $89.00.

I have read post that talked about the need to make changes using the eeprom on the new 996 cluster if you have a 2003 or 2004 Boxster with a MOST system. We don't. If your donor 996 cluster comes from a coupe, a turbo, a C4, or if the PSM system was or wasn't an option on the two cars.

You may want to install the 996 cluster and see where you are.

Others may have more information on this, but for me it was pretty much a plug and play mod. I have PSM in my Boxster and the donor 996 didn't. I need a PST-2 or PIWIS (or a friend that has one) to activate those lights. That is the same tool I believe you use to reset the 996 cluster to a convertable from a couple and to a C2 from a C4.

Good luck and keep us posted.

[lkchris]

So going to CANBus isn't a big deal?

[Chuck W.]

Originally Posted by lkchris

So going to CANBus isn't a big deal?

Well... using a CANBus '03 or '04 996 cluster in our 2001 Boxsters is plug and play. You can't use a CR23 CANBus radio... but the cluster works great.

[emore93]

I have an 01 and replaced the gauge cluster from 2003 996 C2 cab. Other than the things identified by Chuck everything else was plug and play.

I did not need to calibrate the gas gauge or speedometer.

[epapp]

What about pre '00 986? Is the same possible?

[Chuck W.]

Originally Posted by epapp

What about pre '00 986? Is the same possible?

Easy too. You just need to use the early 996 clusters. The 2001 Boxster need the 2003 and 2004 clusters. Pelican has a great DIY on it....

Porsche Boxster 996 Gauge Cluster Upgrade - 986 / 987 (1997-08) - Pelican Parts Technical Article

[mikesz]

I tried to use the eprom programmer thingy not a GQ and damned if I could figure it out. I have a first gen 986 a 99.

[jgaude]

I'm trying to upgrade as we speak.. Having weird issues. Tried the eeprom thing with a cheap programmer of ebay. Won't read the chip...
Mine is an 02 gauge, out on first install, I thought I was pretty good. Everything worked well except my radio and my gas gauge. Okay.. find a guy with a PIWIS, went today, and the piwis can't see my cluster. We reprogrammed the dme to a 996, it took it.. the inst cluster went from a ? to accessible. But when I tried to look at the inst cluster coding, got an error that states I have to do a full scan before I can look at it.. I did about 5 full scans and it just won't show up. So I have no idea what my issues is with the new cluster... I'm pretty sure my cluster is from a C4, and need to change that.. or get rid of it...

Anyone seen this behavior before?

...Joe

[KevinH1990]

This post on Boxa.net (the UK site) may help someone with an "old" style cluster: How to - Upgrade to a 996 Instrument Cluster - How To - www.BoXa.net You may need to register on Boxa.net to read the the thread, but it is free. I saw that some of them were having trouble with generic eprom readers.

Here's a link to a document I uploaded on Rennlist which summarizes what I learned while working on my cluster: Programming a 996 Cluster to Work in a 986 - Rennlist Discussion Forums

I have not worked on a "new" style cluster and the instructions I included in the article were suggested by another post. Here's the original thread I started on this topic: http://986forum.com/forums/general-discussions/43017-carrera-gauge-swap.html I'm not absolutely sure that anyone has made this work on a 2001 or later Boxster.

[Derventium]

You're quite right about needing little programming, the instruments pretty much worked as soon as I plugged them in, with the exception of showing the wrong mileage. Unfortunately, it's not feasable to send the clocks to the US to have the mileage reset. It appears from previous posts that the mileage is stored on the eeprom in two locations as an encrypted file so a cut and paste similar to the earlier clocks should be in order....

Part of the problem is that I'm not sure that my GQ-4X is reading the chip correctly as I appear to have some data missing and it only reads to about line 400. For example, the VIN is missing its last digit and there's no mention of the model number. Also, the two known locations for the encrypted mileage seem light on data. I understand that if the vin/model are incorrect PIWIS has problems reading the instrument cluster so telling the cluster that it's a convertable, fuel tank and speedo calibration (if I ever find out where that data is stored!) won't be possible.

On the plus side, it's really nice to have a clear dot matrix display for the OBC, a nice clear font instead of the itallic Boxster one (an entirely subjective comment!) and having the additional clocks is great as well. Just need to install the oil pressure sender and happy days!