Last updated: May 21, 1998

Speedometer Removal

Date: Wed, 20 May 1998 01:02:38 -0700
From: Stephen Stanley

Removal of speedo console.

I did this in order to recalibrate a 180 kmh speedo into mph. I've attached a copy of a PowerPoint97 slide with the template in a variety of colours. Feel free to add this to the how-to. To fit the template, you need to get to step 9. To line it up, just make sure that 50mph lines up with 80kmh on the original and 100mph lines up with 160kmh. The lowest speed I've put on the mph template is 30mph since below this speed the standard kmh speedo is non-linear.

If you are just replacing warning bulbs etc, then step 8 is as far as you need to get.

Tools required:

Time required:


  1. Open drivers door and window fully, remove cigarette lighter

  2. Disconnect battery (not strictly necessary, but probably safer when messing with the connections on the back of the speedo cluster)

  3. Remove vent panel which is revealed when the door is opened. Pushing a flat bladed screwdriver under the front of this panel will pop the first clip, then the rest can be gently pulled off.

  4. Undo (3) screws from the curved panel under the steering column. (This is the panel with the vent in it). Pull it back towards you to release the clips.

  5. Unscrew (3) screws in the underside of the steering column housing. Note that these are not interchangeable and should be returned to the holes they were removed from. Using a flat bladed screwdriver, pop the top half of this housing off the lower half. The lower half will come away completely, the upper half will stay attached by a wire - leave it there, you just need a bit of movement to completely remove the speedo console.

  6. Remove (2) screws holing in console. One of these screws is visible all the time time, the other is revealed when you execute step 4.

  7. Sharply tug the console towards you to release the clips

  8. There are 7 plugs to remove from the back of the console, from door side inwards:
    	a. Headlamp raising/lowering connector
    	b. Four main connectors
    	c. Cigarette lighter illuminating bulb
    	d. Power leads for cigarette lighter

    Items listed in c. and d. just pull off, those in a. and b. have to be unclipped as well

  9. The console can now be removed completely. To remove the gauge cluster, undo the (4) brass screws from the back of the console. The fronts of the dials can be accessed by undoing the (2) screws that hold the clear plastic cover on. There are a series of clips which need to eased out of their seatings to get the cover off.

  10. Replacement is a reversal of the above. Note that refitting the connectors to pcb on the back of the speedo unit can be simpler if you stand outside the car and look in through the windscreen while reaching in through the open door or window.

    Also be careful when replacing the panel below the steering column. You should make sure that the air vent hose is pushed onto the vent outlet located up behind it before pushing the panel into place.

ftp this file: speedo_template.ppt. I can make this available in other formats if you do not have PowerPoint, but I wanted to leave it in this format since the size (actual dimensions) may change if I convert it. Just drop me a line. --Steve

Apparently the speedo is driven by a pulsed squarewave which pulses both positive and negative volts at a frequency proportional to the speed of the car. The odometer integrates this to turn this into elapsed distance. If you insert some clever electronics to reduce the pulse frequency by 5/8 to convert the speedo to mph, then the odometer follows suit. Obviously since your odometer reads km before you do this, then you will be adding miles to this figure.

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