2000 Relay 2.5d Tacho

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jonw1
Posts: 2
Joined: 23 Feb 2021, 17:56

2000 Relay 2.5d Tacho

Unread post by jonw1 »

HI
I have a 2000 Citroen Relay 2.5d. The Tacho is not working.
Does anyone know where the pickup is?
I have located the cable speedo drive on gearbox, but there are no wires going to it.
The van has an ECU be it a basic one with no obd port
Thanks
Jon
wheeler
Posts: 7588
Joined: 21 Sep 2002, 19:07
x 949

Re: 2000 Relay 2.5d Tacho

Unread post by wheeler »

The pickup for the rev counter should be on the top of the gearbox pointing down onto the flywheel.
jonw1
Posts: 2
Joined: 23 Feb 2021, 17:56

Re: 2000 Relay 2.5d Tacho

Unread post by jonw1 »

Thanks Wheeler. Found it. It's actually on the bottom of the gearbox on mine. Looked for new one and found it listed as crank sensor. I removed and cleaned it and it's working at the moment, if only from 1k revs, but had nothing before. Have to order new one at some point
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white exec
Posts: 7445
Joined: 21 Dec 2015, 12:46
x 1757

Re: 2000 Relay 2.5d Tacho

Unread post by white exec »

That's odd. The sensor on the gearbox is usually for the speedometer, and is referred to as a distance sensor.
The tachometer sensor is shown on Parts as being at the top of the gearbox bellhousing, pointing vertically downward.

Citroen don't help by Parts referring to speedometers as "tachometers", on the English pages anyway.

Strange that your rev counter is now working again. These things can go intermittent, as they generate a really tiny electrical signal. The distance of the sensor tip to the flywheel periphery is also critical (should be 1mm). New ones often have a small 1mm plastic tip, which is installed touching the flywheel, but gets harmlessly worn off on starting up, leaving the correct 1mm gap. With a used one, or one without the spigot, you need to push it in all the way to touch the flywheel, and then withdraw it by 1mm.
Chris