GPS speedometer installation

The odometer and trip meter have been broken in my speedo for quite some time.  The stock speedometer functions but is widely inaccurate.  Changes in tire size, upgrade to 5-speed transmission and 3.91 LSD diff compounded the issue.  I had every intention to get my stock speedo rebuilt/calibrated by North Hollywood Speedometer.  A complete rebuild/calibration from them runs about $200-250 depending on the condition of the speedo you send them.

After talking to some fellow 2002 owners (Garry) at SoCal Vintage 2015 I was made aware of this new electronic gauge.  This gauge uses GPS signals to determine speed.  I discover the cost of the GPS gauge was the same as a rebuild:  The rest as they say, is history.

Speed hut has countless gauge options and possible configurations.  I was a little overwhelmed by all of the possibilities.  Each gauge is custom made.  My design goal was to appear as 'stock' as possible.

Here are the details if you would like to follow my path:

My order number for reference: 89181

GR338-GPS-02T
3-3/8" GPS Speedometer Gauge 140mph (w/ turn signal and high beam)

• Colors: Day - Black dial // White font
  Night - Numbers White Glow
• Font Style: Century
• Tick Style: Standard
• Graphic: -
• Logo: BMW2002
• Custom Text: -
• Pointer: Black Blade White (Glows White)
• Bezel: Stealth Black

My options were: Remote push button. Custom graphic. Turn signal and high-beam LEDs.

 TEASER

I'm VERY happy with the look once installed.  The custom gauge face is nearly a perfect match!  (If only the BMW lettering was spaced a little wider apart. Anal, I know.) The remote push button will be installed in the odometer knob hole.

GPS ANTENNA INSTALL:  Others have mounted the supplied GPS antenna on the rear parcel shelf.  There is certainly enough cable supplied to mount the antenna there.  I have not yet decided the final configuration of my interior, so I opted to install the antenna where the seatbelt warning indicator was originally located.

Hula girl is supervising ;-)

Glad I had an extra-stubby phillips screw driver.

A file folder for template material & a scrap of 14 gauge steel.  (The GPS antenna is magnetic.)

Antenna mount fabricated.  

Painted and ready for install.

Antenna installed.

GAUGE INSTALLATION:  Although not essential, I recommend disconnecting the battery before doing any electrical work to the car.  Remove the gauge cluster.  Use your smartphone or digital camera to take pictures as you work.  You can reference the photos later as a guide when reassembling.

NOTE:  The following procedure is for the two-piece gauge cluster with the faux-wood facia.  If you have a different type of gauge cluster, your installation may be different.

The Speedhut GPS speedo is a very compact and solidly built.  I was surprised how shallow the unit was. 

   

In order to gain access to the speedo, the tach must also be removed because it's rear cover lies on top of the speedo's rear cover.  Loosen and remove the six sheet metal screw around the tach & speedo's perimeter, and then remove tach first, and then speedo. Set the tach aside. (Be careful of the needle!)

Although the mechanical speedo is being replaced, the back cover needs to be reused because it has the mounting studs that retain the entire gauge cluster.

Loosen the large nut around the speedometer drive.  Remove the nut, washer and back cover.

Store your original speedo in a safe place incase you need to revert back someday.

Front view - Cluster with speedo and tach removed.

Next, remove the odometer reset knob.  Remove the e-clip from the back and the knob pulls out from the front.

The glass and bezel/locking ring must be removed from the speedometer opening.  To remove the glass from cluster in front of the speedo, the bezel/locking ring must first be removed. The picture above is of the tach opening and is for EXAMPLE only. Only the glass in front of the speedo needs to be removed. The bezel/locking ring locks into position by cutting into the black plastic tabs that hold the cluster facia to the cluster.  To remove the bezel it must be turned counter-clockwise.  There are two notches (11 & 5 o'clock pictured above) in the bezel.  Use a large flat blade screwdriver to rotate the bezel.  Be cautious, the bezel/locking ring will require a lot of force to turn.

Speedo bezel/locking ring removed.

OPTIONAL PROCEDURE:  If you want to paint, or otherwise recover your gauge cluster's facia, now is the time to do so.  Remove the combo gauge and set it aside.  Remove the bezel/locking rings from all of the gauge openings.  Carefully pull the facia off, while at the same time, releasing the black clips from the back.  A few of the clips broke off while I was disassembling mine. I was able to superglue them back into place without difficulty. (If any of the clips around the speedo broke off, don't bother gluing them back on.)  Don't forget to clean all of the glass!

The tabs around the speedo ONLY must be removed.  Break them off FLUSH with the back of the facia. NOTE:  It is not necessary to remove the facia from the cluster to break off the tabs around the speedo.

It's important to understand how the GPS speedo is installed before continuing.  Look closely at the the pictures above.  The openings in the gauge cluster (top) are slightly larger then the openings in the facia (bottom).  The intent is for the GPS gauge to fit snugly THROUGH the opening in the cluster and REST flush AGAINST the back of the opening in the facia. Check your fitment.

If you completely disassembles your facia/cluster to perform the OPTIONAL PROCEDURE above, reassemble it now before continuing.

The GPS speed must sit flat against the back of the FACIA.  I recommend trail fittings throughout this step to insure the gauge sits flush.  The two areas, circled in red in the picture above, needed to be ground so the GPS speedo would fit into the cluster opening.  Do NOT cut/grind into the facia.

Hold the GPS speedo in place and check for proper fitment from the front.  Proceed when you are satisfied.

There is no room to utilize the threaded locking ring that came with the gauge.  I considered SEVERAL options to secure the GPS speedo into the cluster before finally deciding to use hot glue. There may be a more eloquent mounting solution, but this was quick and effective.  I had a helper for this step.  While one person held the gauge in perfect alignment, the other applied the hot glue. Make sure the gauge is pressed fully/firmly into the cluster/facia so there are no gaps around the GPS bezel.

I mounted the GPS speedo's select button into the hole where the original odometer knob was located.  Look closely at the opening in the facia, it is tapered.  I ground the nut that came with the button until it just fit into the opening.  A tight, friction-fit.  I pushed the button in from the back and rotated it into the nut until it was tight.

I didn't like the look of the chrome, so I painted it semi-flat black.

Included with the GPS speedometer is a small transformer that is required for the gauge illumination. It has double-sided tape on one side.  I mounted it directly to the back of the speedo.  I connected the plug to the corresponding connector on the speedo.

Here is a pic of all of the wiring, including the GPS antenna cable, before reassembling the cluster.

I added a rubber grommet to the opening protect the wiring.  Completely reassemble the cluster.

WIRING: The gauge comes with an electrical diagram.  The following electrical connections are required:  Ground, +12VDC (On with ignition), and +12VDC (On with lighting).  Optionally you may connect +12VDC (Constant power) to speed up the GPS speedometer's satellite acquisition time.

NOTE:  The +12VDC for the gauge lighting can NOT come from the dim-able dash light circuit.  It must be a full +12VDC to operate the transformer.  There is a spare tap on the headlight switch that can be utilized for this.

The picture above is of the electrical connector on the headlight switch.  Notice the empty tap in the upper left.  This tap is hot when the lights are switched on.  This tap may be used to supply +12VDC to the Speedo's illumination transformer.

I used shielded spade and/or bullet connectors for all the wiring I added so that the cluster could be easily removed again if necessary.  I tied up the extra antenna cable behind the dash in front of the heater box.  Reconnect the battery if you disconnected it earlier, reinstall the cluster and enjoy your new speedometer!

CLUSTER REINSTALLED:  I am VERY pleased with the installation.  I did not have time to connect the turn signal LEDs nor the high beam LED.  These will have to wait for another time.  I also did not connect the +12VDC constant power.  This wire provides for nearly instant satellite acquisition.  During my research I had read the gauge was too bright.  I think the gauge brightness it just right.  In a future upgrade I will replace the bulbs in the other gauges with white LED strips to match the speedo.

DIFFERENT DISPLAY SCREENS

These are the different screens/modes the gauge has.

Startup

Acquiring satallites 

Odometer and trip meter

Odometer and clock

Odometer and elevation

Odometer and current speed

Odometer and Compass

Peak speed (Needle indicated too.)

0-60 times (Looking forward to testing this feature.)

1/4 mile times

Speed hut info

KEEP CHECKING BACK...  I WILL FILL IN MORE DETAILS AS I GET TIME