VDO Tachometer fitting in Td5 Defender - Lowtension

Images and text © Lowtension - www.lowtension.com. Taken, with permisson, from VDO Tachometer project guide.

The tachometer is available as a complete kit from Lowtension - this comprises of a calibrated 52mm 6000 RPM tachometer, green illumination, screw ring and fitting instructions. £49.99 inclusive of vat and postage.

Many thanks to Tony Boyle, all of the images are taken from his Td5 and his help was invaluable in the construction of this project kit.

Td5 owners have contacted me asking whether there is a suitable tachometer that will fit straight into the existing instrument pack and match the other instruments - the answer is our Td5 tachometer kit.

The tachometer output from the Td5 ECU is very low - even measuring with an oscilloscope the signal is small. We have boosted the DC offset to the standard VDO tachometer to enable it to function in the same way as the original equipment tachometer.

	This is the existing instrument combi with the standard fuel gauge, temperature and clock layout.
And this is where we want to get to with the fuel gauge and temperature moved over one place to the right, the clock removed (this can either be reintegrated into the dashboard or many audio units already have a clock fitted) and the VDO tachometer is inserted into the first position. Notice that the pointer of the tachometer is orange, the night time illumination is through lit green - matching the other instruments.
	The combi is completely removed from the TD5 by removing the four screws (two each side and two underneath). The combi is then carefully unplugged from the main harness for modification.
The tachometer will need a signal to drive it, and this is available from the ECU located under the driver's seat. If you are lucky, there will be a White/Grey trace wire already at the plug up at the instrument harness. Otherwise you can connect directly to the ECU at the BLACK plug - the correct pin is number 19, located centrally at the plug.
	Now at the Combi, we remove all of the tape covering the harness and also the green tape covering the power connection to the instruments. The clock is removed and the small harness cut away.
The instruments are unplugged individually and moved one position. The lamp holder for the fuel becomes the lamp for the tachometer and the new lamp holder and power connections for the tachometer are soldered into the harness. (These parts are all contained in the kit.)
	The connections and the harness are re-taped. It is worth checking at this point that the instruments are sitting squarely - if necessary they can be rotated from the back.
Finally, the Combi is fitted back to the TD5, the signal connection from the ECU is plugged into the tachometer, all plugs fitted and the Combi screws replaced - All that remains is to start the engine and watch the needle respond!

Back to Td5 KB