Pelican Technical Article: 996 Gauge Cluster Upgrade Wayne R. Dempsey
Time: 4 hrs
Tab: $600
Talent:
Tools:
Torx driver set
Applicable Models:
986 Boxster (1997-04)
Parts Required:
Cluster, oil pressure sender, VW pin wire
Hot Tip:
Buy your cluster from a legitimate used parts dealer
Performance Gain:
Voltmeter, oil pressure gauge
Complementary Modification:
On board computer
This article is one in a series that have been released in conjunction with Wayne's new book, 101 Performance Projects for Your Porsche Boxster. The book contains 312 pages of full color projects detailing everything from performance mods to changing your brake pads. With more than 950+ full-color glossy photos accompanying extensive step-by-step procedures, this book is required reading in any Boxster owner's collection. The book is currently available and in stock now. See The Official Book Website for more details.
Check out some other sample projects from the book:
One of the neat upgrades that you can perform on your Boxster is to install the Porsche 911 (996) gauge cluster into your dashboard. The 996 cluster has two additional gauges, a voltmeter and an oil pressure gauge that you can hook up and make operational. In addition, the later-style 996 gauges have an improved dot-matrix style screen that is an upgrade from the original style. The actual swap of the gauge cluster is not very difficult, but there are some elements of the entire project that can be challenging.
Which cluster to purchase?
The first difficulty lies in figuring out which 996 gauge cluster to purchase for your Boxster. There were several different clusters manufactured for both the Boxster and the 996, and only some of them are compatible with each other. In general, there are two different types of clusters, an early-style, and later improved-style with a dot-matrix display. The 1997-00 Boxsters can only use the early style, and the 2001-04 Boxsters can only use the late-style. You can easily tell the difference between the two by the color and shape of the connectors on the back of the gauge cluster. Early-style clusters have a blue, white and black connector. Late-style clusters have connectors that are grey, blue and green. The two different types of clusters are not interchangeable.
I recommend that you purchase your used cluster from a reputable used parts dealer. I'm guessing that a lot of the gauge clusters that end up on classified and auction sites might be rejects from warranty replacements. The gauge clusters can be very expensive (I paid $500 for mine from a used parts dealer), so making sure that you get one from a reputable source is very important. The cluster I used for my Boxster came out of a wrecked 996.
In addition, you must make sure that you match the transmission type and region type. If you are located in the United States, be sure that you get a cluster that is a US-spec unit, and has the main speedometer gauge delimited in mph. European gauges will show km/h. Also be sure that you purchase a cluster that will match the type of transmission you have. The Tiptronic clusters are different than the manual transmission ones because they have the current gear selector display on the right side of the cluster.
For the 1997-00 Boxster, you need to find an instrument cluster from a C2, not a C4. This is because the early C4s have a different gas tank and a different fuel sending system that is not compatible with the Boxster. If you install an early C4 cluster into an early Boxster, then your fuel gauge will not operate properly. In addition, the very early C2 cars used a different fuel level sender than the one that is used in the Boxster. As a result, installing an early C2 cluster into a Boxster may not give you the most accurate fuel gauge reading (although I did install one on my project Boxster, and it appears to be working okay). Also, the On Board Computer (see Pelican Technical Article: On Board Computer (OBC) Upgrade), was not always included as standard equipment in the early Carreras: if you get a cluster from a car that doesn't have the computer built-in, then you will need to turn it on with the PST-2. For these reasons, I recommend using a cluster from a 2000-01 Carrera 2. Part numbers have changed over the years, but two sample part numbers for this range are 996-641-105-02 (manual), and 996-641-106-02 (Tiptronic). The cluster may have an additional code at the end of the part number which is the color code (70C corresponds to black, for example).
For the 2001-04 Boxster, you can use any non-Turbo 996 cluster from the years 2002-04. This can be from a C2 or a C4: the clusters were modified in these later years to eliminate the problems that were inherent with the earlier C4 clusters. Ideally, you should try to find a cluster from a cabriolet car, so that you won't have to recode the cluster to enable the convertible top lamp (coupe clusters can be recoded to make the convertible top lamp operational). As with the earlier cars, be sure to match the cluster with your transmission type (manual vs. Tiptronic). The On Board Computer was standard equipment on all 2002-04 Carreras, so the best cluster to use is one from a convertible within the year range of 2002-04. I also highly recommend that you install the control switches for the on board computer (see Pelican Technical Article: On Board Computer (OBC) Upgrade). A cluster from a 2001 Carrera is not correct for a 2001 Boxster: use a 2002 or later cluster. Part numbers have changed over the years, but two sample part numbers for this are 996-641-980-20 (manual) or 996-642-980-21 (Tiptronic).
Which gauge pod to use?
There are two methods you can use to physically install the gauge cluster into the dash of your Boxster. The standard Boxster gauge pod has a bridge that extends over the gauges so there's a gap between the gauges and the top of the pod. The 996 gauge pod does away with this bridge. You can purchase the 996 cluster with the corresponding 996 gauge surround, but then you lose this cool-looking bridge between the gauges and the top of the pod (the 996 doesn't have this). The 996 gauge pods are also very expensive. If you do go this route, be sure to get one that matches the interior of your car, and also get the hazard switch and surround included as these are different on the 996 pod.
For my car, I preferred to modify my own gauge pod. Basically, you take the existing Boxster pod and cut away some of the plastic to make the 996 cluster fit. This keeps the bridge look of the Boxster pod and also saves you a considerable amount of money because you don't have to purchase a 996 gauge pod. The trimming procedure is straightforward, but it requires some attention to detail and a bit of patience to complete properly. See Photo 4 for details.
Installation
Before you begin the installation, I recommend that you make sure the car has a tank of gas that is more than one half full. There have been sporadic reports of the clusters becoming slightly confused when installed and reset with a tank of gas that is less than half empty. I recommend making sure you have about Ύ of a tank prior to installation. To prepare your gauge cluster, make sure that it has a light bulb installed in the convertible top lamp holder (for 2001 and earlier 996 clusters). If your cluster came from a coupe car, then there probably won't be any bulb installed there.
The first step is to disconnect the battery (see Pelican Technical Article: Battery Disconnect Switch / Battery Buddy Installation). Then, remove the Boxster cluster (see Photo 2 and 3). Then remove the access panel to the engine compartment behind the seats (see Pelican Technical Article: Drive Belt Replacement), and also the engine compartment lid under the convertible top (see Pelican Technical Article: Air Filter / Pollen Filter Replacement). The Boxster engines only have an oil pressure switch which turns on a warning lamp on the dash when the oil pressure drops below a certain level. In order for the 996 cluster's oil pressure gauge to function properly, you need to install the 996 oil pressure sender in place of the Boxster oil pressure switch. Using a 24mm deep socket, remove the oil pressure switch as detailed in Figure 6. Install the new oil pressure sender (part number 996-606-203-01) using a 24mm crowfoot wrench. Do not turn the sender by the outer case: doing so can damage the sender. Attach the existing wire to the WK terminal on the oil pressure sender. This wire sends the signal for the low oil pressure switch.
Now it's time to run a signal wire from the back of the gauge cluster all the way to the new oil pressure sender in the engine compartment. Remove the shifter cover and the armrest as detailed in Pelican Technical Article: Installing a Short Shift Kit and Replacing Shift Bushings. Poke a hole in the rear shifter cable grommet that feeds the cables into the engine compartment. Thread the signal wire through this hole. Secure along its way with zip ties (see Figure 7). Run the wire all the way up to the front of the car, and through the center console. See Project 75 for more information on removing the center console. With the wire laid out, reinstall the shifter, the center console, and the armrest. Be careful not to get it pinched under the shifter or under the arm rest when you reinstall them. Crimp a spade connector on the end of the wire in the engine compartment and attach it to the G terminal of the oil pressure sender.
The oil pressure sender signal wire needs to be attached to one of the pins in the gauge cluster. Affix it to the bundle of wires that go into the blue connector using a zip tie or two. Pelican Technical Article: On Board Computer (OBC) Upgrade, Installing the On Board Computer, has all the details on how to insert the wire into the plug on the rear of the gauge cluster. Use the same Volkswagen mini-wire harness (Part Number 000-979-010), and remember to install the proper end into the connector. For the 1997-00 Boxster, the oil pressure sender wire needs to be tapped into pin 9 of the blue plug. For the later cars, 2001-04, the wire should be inserted into pin 5 of the blue plug.
With the cluster plug properly wired, temporarily install the new 996 cluster into your Boxster and turn on the ignition key. It's important to note that you don't want to do this if you've removed your steering wheel and airbag, as this will cause your airbag light to come on (which will have to be reset by the dealer or aftermarket software). With the ignition key on, you should see the voltmeter operating properly as well as the oil pressure sender (should be at zero). If the oil pressure gauge pegs to the top of the gauge, the connection is broken and you have a problem with the signal wire: time to troubleshoot it with a multimeter. If you start the car, the oil pressure gauge should go up to 4 or 5. If the gauge doesn't operate properly, you might try removing and reseating the connectors. When I installed my gauge, I was working on the 3.4 996 engine swap at the same time, and I hadn't connected the ground strap yet, which caused the oil pressure gauge to peg. Make sure your ground strap is properly fastened (see Photo 1 of Pelican Technical Article: Battery Disconnect Switch / Battery Buddy Installation).
Once you have confirmed that the new cluster works properly, you should modify your Boxster gauge pod. I don't recommend modifying it until you have at least confirmed that the 996 cluster works.
Reprogramming the cluster and radio
Depending upon which cluster you purchase, you may or may not need to go through a reprogramming procedure using the Porsche PST-2 or PIWIS factory programming tool (see Pelican Technical Article: On Board Computer (OBC) Upgrade). Most people don't have this, so you may need to buddy up with your local Porsche dealership, or find a local independent shop that has one and is willing to work on this with you.
Boxster guru Todd Holyoak has developed the following programming system for updating the gauge cluster in the Boxster:
Connect the PST2 or PIWIS tester and select model 996 and the DME module
The only option available to you will be to reprogram the DME
Reprogram the DME using the immobilizer and DME programming codes. Use the codes that you received from your dealer, and enter the same values for the old and new codes when the PST2 requests them.
After programming, enter the vehicle data tab
Recode the model type to 911 C2 cab , use 911310 for North America, or 911311 for Rest Of World (ROW)
Back out to the original screen and perform a complete control module search
Enter the instrument cluster tab, and change any coding you would like (cruise control, On Board Computer, cabriolet set, etc)
Exit back to the original screen
Recode back to your original 986 type using the current DME and immobilizer codes you used previously.
This procedure should allow you to change all of the settings in the 996 cluster to work with your Boxster. If for some reason you are not able to get this procedure to work, another solution is to install the gauge cluster into an existing 996 car and then reprogram it there. Of course, it's pretty difficult to find someone willing to let their 996's dashboard be taken apart for this purpose.
Unless you have purchased a new gauge cluster delivered in a sealed Porsche box, the cluster will have the mileage from the donor car programmed into it. The only way to reset the mileage on the gauge pod is to send it to a speedometer shop well versed in the secrets of how to reprogram the clusters. Palo Alto Speedometer currently charges about $200 to program the cluster and reset the mileage to a different amount. If you have a brand new gauge cluster, then you can use the PST2 tool to set the mileage. After about 50 miles or so on the odometer, the gauge cluster will be locked and you will not be able to reprogram it any more.
For the radio, Boxster models from 1997-2002 will only need to tap in the four-digit radio code into the radio in order to make it functional again. The 2003-04 Boxsters are installed with a new multimedia communications bus system called Media Oriented Systems Transport (MOST). The Porsche implementation of this system did away with the use of a radio code, and instead the radio looks to the gauge cluster for VIN information. If there is a match, it will turn the radio on. When you install a new cluster into a MOST-equipped car, the radio will display PORSCHE PROTECTED. You can fix this problem by reprogramming the cluster with the new VIN information. If you are reprogramming the DME using the procedure documented above, then you can fix this problem by running the Sports Car Handover routine in the PST-2 tool. This is the delivery routine that is run by the Porsche dealer when the cars are received by the dealer off of the delivery truck.
Figure 1
Shown there are the Boxster gauge cluster (top) and the 996 cluster (bottom) side-by-side. As you can see, they are almost exactly the same, with the Boxster cluster simply missing the additional voltmeter and oil pressure gauge.
Here are the steps for removing the cluster. A- Pull out the microphone cover and remove the torx screw underneath. B- Pull out the hazard switch button and remove the torx screw underneath. C- Using some long pliers, grab the white plastic part of the hazard switch (shown in B) and pull it out of its plug (press on the two black tabs on either side of the white plastic switch and pull in the direction of the red arrow). Then, slide the black connector in the direction of the green arrow. D- Lift the gauge cluster up so that you can disconnect the wire harnesses on the back (see Figure 3).
This photo was shot through the front windshield and shows the three connectors on the back of the gauge cluster that you need to disconnect in order to remove the cluster. Press on the small tab of each connector (green arrow), and then pull the retaining clip up (yellow arrow), and the connector will automatically pull out of the back of the cluster.
Here are the steps I used for adapting the Boxster gauge pod for use with the 996 cluster. A- Line up the new cluster with the old plastic surround and mark the area that needs to be removed with a pencil. B- Here you can see the pencil line (green arrow). The surround needs to be trimmed out to the wall of the plastic enclosure (red arrow). C- Use a Dremmel tool to carefully grind the plastic until you meet the contour curves. D- Here's the backside of the surround with the appropriate amount of plastic removed. E- Here's a close-up of the final cut. Not too shabby! F- Here's the complete 996 cluster encased inside of the modified Boxster gauge pod.
This photo shows the 996 gauge cluster installed in the Boxster. The 996 gauge gives you the voltmeter on the left and the oil pressure level on the right (the gauge is pegged because the sending unit is not installed yet).
This photo of the Boxster engine compartment shows the oil pressure switch (green arrow) and its connector disconnected from the sender's spade terminal (yellow arrow). The inset photo shows the 996 oil pressure canister, which contains both a low-pressure switch and a variable oil pressure sensor that powers the module in the 996 gauge. Terminal G supplies the signal for the oil pressure gauge, while terminal WK provides the low oil pressure switch signal.
It's fairly easy to run the signal wire for the oil pressure sender down the center tunnel of the car. In the engine compartment, poke a hole in the rubber boot that holds the shift cables (yellow arrow). The inset photo on the bottom shows the armrest and the shifter console cover removed: route the wire through here and use zip ties to secure it to the shift cables. The upper inset photo shows the bottom portion of the center console that you can remove to help feed the wire up through the dash board.
You apparently missed this statement in my Renntech write-up while developing your procedure:
"For example, fuel gage problems with a C4 cluster due to fuel tank design or oil quantity/car leveling errors with a Turbo cluster due to engine sump differences were some of the problems to be avoided."
The oil quantity can not be displayed electronically, on the instrument cluster, prior to starting the engine if a TT instrument cluster is used. I believe the TT has a "dry sump" oil system.
Bill
February 7, 2012
Followup from the Pelican Staff: Actually, I do mention that in the text above (5th paragraph) - don't use a Turbo cluster, and don't use a C4 cluster. Thanks for helping to clarify for everyone else. - Wayne at Pelican Parts
Check out some other sample projects from the book:
