Carrera Gauge Swap - 986 Forum - The Community for Porsche Boxster & Cayman Owners

KevinH1990 · 02-03-2013, 08:08 PM

I am continuing my effort to install a Carrera Gauge cluster in my 2000 Boxster. The Carrera cluster has a damaged clock/oil gauge lcd and you can see here:

I haven't found anyone who can repair a broken lcd, so I thought I would try installing the Carrera Gauge faces on my Boxster circuit board. You can see the results here:

When I use the Carrera gauge faces on the Carrera Board, everything works OK with the exception of the damaged lcd. (It works, but it is unsightly.)

When I use the Boxster circuit board, every works OK except the voltmeter. As you can see in the first picture, the Carrera/Carrera combination reads between 11 and 12 volts when the ignition is switched on. The second picture shows that the Carrera/Boxster combination reads 0 when the car is on.

(When the car is running, the oil gauge reads between 4 and 5 with either combination.)

Any suggestions on what I might try next? The circuit boards appear identical and have the same part number. However, there are so many components on each that it is not possible for me to be sure they are identical.

In this photo, the Carrera circuit board is on top and the Boxster is below.

Deserion · 02-04-2013, 05:16 AM

I'll preface this by stating I'm not overly familar with the Carrera gauge swap.

That said, could it be a coding issue when using the voltmeter on the Boxster's circuit board? It made sense when I typed it anyway...

ChrisZang · 02-04-2013, 05:50 AM

Kevin,

I would look for a bad connection

KevinH1990 · 02-04-2013, 06:39 PM

Thanks for the suggestions. I tried re-seating the connections and that didn't help. I also hooked up my Durametric. I used the test functions for the gauge cluster in hopes that a little exercise would get it started, but no luck.

Here's what I know:

1. The voltmeter works fine when it is hooked up to the Carrera circuit board that came with it. This means that:

A. The Carrera gauge itself is not broken
B. The car is sending the correct signal to the Carrera circuit board.
C. The connectors from the car to the Carrera circuit board are OK.
D. The connectors between the Carrera circuit board and the Carrera gauges are OK.

2. All the gauges and lights work correctly using the Boxster circuit board and the Carrera gauges with the exception of the voltmeter. This means that:

A. The voltage signal is not being transmitted from the Boxster circuit board to the voltmeter; or
B. The Boxster circuit board is not processing the signal from the car correctly; or
C. The pin for the Carrera circuit board to receive the signal is different than one on the Boxster circuit board
D. The signal from the car is not passing to the Boxster circuit board.

I'm continuing to try to figure this out. There is a shop in California (Palo Alto Speedometer) that specializes in this kind of thing. They couldn't fix the burned out lcd on the cluster I bought because they can't obtain the parts, but they may be able to fix this. Someone on Pelican suggested a speedometer shop in my area that works on VDO gauges. I will definitely give them a call. I'm also going to check with Hollywood Speedometer.

I'd appreciate any other suggestions.

idheaton · 02-04-2013, 09:39 PM

I am guessing you already thought about this but since I did not see it mentioned I will throw it out there. Is it possible to swap he boxster lcd onto the carrera board?

KevinH1990 · 02-05-2013, 03:16 AM

Quote:

Originally Posted by idheaton

I am guessing you already thought about this but since I did not see it mentioned I will throw it out there. Is it possible to swap he boxster lcd onto the carrera board?

It will take someone with soldering skills/knowledge above my level. But, I'm planning to ask a speedometer shop in my area if they can do it. I don't want to have both units damaged so I'm not going to try it myself.

Thanks

Reebuck1 · 02-20-2015, 10:06 AM

Thumper the reason I am having so much trouble ( I believe...not sure) is because I have 5.2.2 DME.

I think I have now successfully recoded the EPROM chip on my 986 mother board to "TURN ON" the volt gauge and oil pressure gauge.
Topradio, your suggestion to try different chip designators on the GQ-4X worked and I was able to read the chip.

I reinstalled the 986 mother board with the 996 gauges but volt and oil pres. still will not come on. Maybe because the 986 DME that thinks it is a 996 ROW will not recognize the 986 mother board??

Topradio, I am wondering if I need to also code the bits with the GQ-4x that identifies the gauge pack mother board as a 986. This is found on line 00000030 of the code as shown on post #15 and #13. ???? If I change that bit to indicate it as a 996 do you think it will work??

Does anyone know if there is a limit on the number of times you can try and reprogram one of these EPROM chips??

I still intend to put the 996 mother board back in car and take it to Porsche to turn on the cruise control.

Reebuck1 · 02-21-2015, 10:53 AM

Guys, Hoping I can get answers from some tech savvy folks out there to my questions below.
Even if you are not sure give me your thoughts and they could be the answer. Thanks

I reinstalled the 986 mother board with the 996 gauges but volt and oil pres. still will not come on. Maybe because the 986 DME that thinks it is a 996 ROW will not recognize the 986 mother board??

I am wondering if I need to also code the bits (with the GQ-4x) that identifies the gauge pack mother board as a 996. This is found on line 00000030 of the code as shown on post #15 and #13. ???? If I change that bit to indicate it as a 996 do you think it will work??

Does anyone know if there is a limit on the number of times you can try and reprogram one of these EPROM chips??

KevinH1990 · 02-06-2013, 05:30 PM

I went by the local company - Southern Electronics - today. They don't have the equipment to work on the "new" Porsche speedometers. Since this style of speedometer first appeared in 1996, the term "new" covers a lot of territory. They referred me to a guy in Chicago - Best Pixel Repair. He does replace lcd's but only on BMW's. He said the parts for Porsches are unavailable.

Right now I think I have two options:

1. See if a shop with a PIWIS can "turn on" the voltmeter on my hybrid Boxster/Carrera cluster. I'm not sure how that might work but maybe there is something in the software. I checked with my Durametric and that didn't work.

2. Check with Palo Alto Speedometer or North Hollywood Speedometer to see if they can make the voltmeter operational on my Boxster/Carrera cluster.

I paid $150 for the cluster, so I hate to see it go to waste. Maybe someone will need some parts and I can recoup some of the money.

ChrisZang · 02-07-2013, 08:37 PM

Kevin, real sorry about that. I wish I hadn't given my old two clusters away for basically nothing. I don't think that Palo Alto speedo is an option. This will cost you several hundred dollar, almost cheaper to find a spare cluster.

KevinH1990 · 02-08-2013, 06:02 PM

Quote:

Originally Posted by ChrisZang

Kevin, real sorry about that. I wish I hadn't given my old two clusters away for basically nothing. I don't think that Palo Alto speedo is an option. This will cost you several hundred dollar, almost cheaper to find a spare cluster.

If I recall your posts correctly, I think you had the "new style" cluster, so it wouldn't have been compatible. I don't think Palo Alto or North Hollywood can help based on their responses. I'm still planning to talk with a local independent who has a PIWIS to see if they can activate the voltmeter in my merged Boxster/Carrera cluster. I think that is a long shot, but I"m an eternal optimist.

Oh well, I went into this with a "low-risk, high reward" attitude. I think I can recoup some of the money on the cluster I have if someone needs parts, and I can keep looking for a good used cluster so my investment in the oil pressure sending unit won't be wasted.

gavinyuill · 02-12-2013, 11:36 AM

I have done this and can tell you it is due to the programming on the console eprom.

I am a bit of a electronics nerd and used an eprom programmer and a 8 pin clip to copy off the old programming and copy the programming from the 996 cluster onto the boxster chip. the voltmeter works perfectly now, but the fuel gauge is very slightly low. I am planning on doing some experimentation soon to find out what to change on the programming to get it working.

If you want to ship both clusters to me I am happy to copy one to the other for you. I can update mileage as well. Not sure if I can test it as I have a 97 with the old style connectors. I'm also happy to point you in the direction of what to buy (around $250 (Edit - just found a cheap chinese version on ebay for $47)) and how to do it if you want a DIY solution.

PM me for details.

KevinH1990 · 02-23-2013, 12:15 PM

Gavin,

As we discussed on the phone, your method worked perfectly. The proof is in the picture.

If anyone needs the equipment to update a Boxster cluster so that it can support a set of 996 gauges, let me know. I'll give members on the 986 Forum first shot before I put it on Ebay.

Jaxonalden · 02-24-2013, 08:06 AM

KevinH1990,

PM sent on what you have to offer.

KevinH1990 · 02-24-2013, 05:59 PM

Here's some information for anyone who wants to repair a defective 996 cluster (for example my 996 cluster had a bad lcd) with the good circuit board from a 986. The benefit for me was that I was able to perform the 996 cluster swap by using a defective cluster that cost me $155. It looks like non-defective 996 clusters cost $500 or more, so the savings are significant. In addition, you can swap over the mileage from your Boxster without sending it a speedometer shop. One shop is charging $200 for this service. Gavin Yuill was the person who figured this all out, so he should receive the credit.

Please note - I did this using a cluster from a 2000 996 and a 2000 986. These are the "old style" clusters with the blue, white and black connectors. I don't know if it will work with the "new style" clusters. Also, if you try this at home, you assume all the risks.

The good news about swapping the circuit boards is that the MY 2000 986 and 996 circuit boards are identical. The bad news is that the programming in them is different. In my case, this meant when I attached my 986 circuit board to my 996 gauges the voltmeter didn't work. I also expect that the analog speedometer would be off by a bit and the mileage would be incorrect.

As Gavin says in his post, the way around this is to copy the programming from the 996 circuit board and write it to the 986 circuit board. At the same time, you can copy 3 lines of code from your 986 and use it to update the mileage and the Vehicle Identification Number from your Boxster. You can probably also turn on the cabriolet top operation light and the on board computer as well. However, I did not have to do this in my car. Perhaps Gavin can share this information too.

In order to do this, you need a device called an Eprom programmer. You also need a clip to attach the programmer to your circuit board. On my model year 2000 circuit boards, the chip is above the center lcd and slightly to the left. Here's a picture of the set up:

Here are the basic steps you will follow:

1. Connect the programmer to the Carrera circuit board.
2. Download the programming from the Carrera cluster and save it to a file. (On the EPROM programmer I bought I was required to "swap bytes" when downloading. There is a selection in the programmer software that does this automatically.)
3. Disconnect from the Carrera circuit board and connect to the Boxster circuit board.
4. Download the programming from the Boxster chip.
5. Copy the first line of the Boxster programming and use it to overwrite the first line of code in the file containing the Carrera coding. (This contains the odometer reading. It's encrypted, probably as a deterrent to odometer fraud.)
6. Copy the second half of the second line of the Boxster code and copy it to the second half of the second line of the Carrera code. Copy the first half of the third line of the Boxster code to the first half of the third line of the Carrera code. This updates the VIN.
7. Save the modified code to a new file.
8. Write the modified Carrera code file to the Boxster chip
9. Reassemble everything and you're done.

Here's a picture of the computer code that I copied from my Carrera chip. Note how the VIN starts in the middle of the second line and ends in the middle of the third line.

Note that the EPROM programmer and the clip to connect to the board cost about $140 shipped. I'm willing to sell mine at a discount to anyone who needs to do this. Just send me a PM if you are interested.

jgama25 · 04-11-2013, 01:37 PM

Quote:

Originally Posted by KevinH1990

Here's some information for anyone who wants to repair a defective 996 cluster (for example my 996 cluster had a bad lcd) with the good circuit board from a 986. The benefit for me was that I was able to perform the 996 cluster swap by using a defective cluster that cost me $155. It looks like non-defective 996 clusters cost $500 or more, so the savings are significant. In addition, you can swap over the mileage from your Boxster without sending it a speedometer shop. One shop is charging $200 for this service. Gavin Yuill was the person who figured this all out, so he should receive the credit.

Please note - I did this using a cluster from a 2000 996 and a 2000 986. These are the "old style" clusters with the blue, white and black connectors. I don't know if it will work with the "new style" clusters. Also, if you try this at home, you assume all the risks.

The good news about swapping the circuit boards is that the MY 2000 986 and 996 circuit boards are identical. The bad news is that the programming in them is different. In my case, this meant when I attached my 986 circuit board to my 996 gauges the voltmeter didn't work. I also expect that the analog speedometer would be off by a bit and the mileage would be incorrect.

As Gavin says in his post, the way around this is to copy the programming from the 996 circuit board and write it to the 986 circuit board. At the same time, you can copy 3 lines of code from your 986 and use it to update the mileage and the Vehicle Identification Number from your Boxster. You can probably also turn on the cabriolet top operation light and the on board computer as well. However, I did not have to do this in my car. Perhaps Gavin can share this information too.

In order to do this, you need a device called an Eprom programmer. You also need a clip to attach the programmer to your circuit board. On my model year 2000 circuit boards, the chip is above the center lcd and slightly to the left. Here's a picture of the set up:

Here are the basic steps you will follow:

1. Connect the programmer to the Carrera circuit board.
2. Download the programming from the Carrera cluster and save it to a file. (On the EPROM programmer I bought I was required to "swap bytes" when downloading. There is a selection in the programmer software that does this automatically.)
3. Disconnect from the Carrera circuit board and connect to the Boxster circuit board.
4. Download the programming from the Boxster chip.
5. Copy the first line of the Boxster programming and use it to overwrite the first line of code in the file containing the Carrera coding. (This contains the odometer reading. It's encrypted, probably as a deterrent to odometer fraud.)
6. Copy the second half of the second line of the Boxster code and copy it to the second half of the second line of the Carrera code. Copy the first half of the third line of the Boxster code to the first half of the third line of the Carrera code. This updates the VIN.
7. Save the modified code to a new file.
8. Write the modified Carrera code file to the Boxster chip
9. Reassemble everything and you're done.

Here's a picture of the computer code that I copied from my Carrera chip. Note how the VIN starts in the middle of the second line and ends in the middle of the third line.

Note that the EPROM programmer and the clip to connect to the board cost about $140 shipped. I'm willing to sell mine at a discount to anyone who needs to do this. Just send me a PM if you are interested.

Perfect Perfect Perfect for what I need!!!!
I too have a busted LCD screen and I've been looking for an easier fix than buying a brand new cluster.

Kevin/Gavin Thank you for posting this!!!

Trey T · 09-08-2013, 07:10 PM

whats the coolant temp value bt 180 and 250? is it 215?

I have never figure out why there's no middle mark to make reading easier and friendlier. The SO drives the boxster and I have to tell her to watch-out the temperature, the needle b/t the 8 and 0 is operating temp.

mikesz · 06-11-2016, 03:47 AM

Hi Kevin, first off new LCD panels appear to be available and being sold on ebay. If you don't want to go that route you may want to contact Steve at Qumulus in Colorado he says he can fix damaged LCD's. He has my Boxster gauges and 996 cluster when I gave up trying to program it with the EPROM.

ChrisZang · 02-25-2013, 06:48 AM

KevinH1990 · 02-25-2013, 06:22 PM

I put it all together and took it for a spin. Everything seems to be working perfectly. I even filled up the gas tank and 4 gallons took it from about 3/4 full to full.

This is a picture showing a better view of the programmer is attached to the board.

Here's a shot of the computer screen showing the data and software right after a read of the chip.