blog.jamesbaber.co.uk

Fixing the tachometer LCD in a MINI (R50, 2001 MINI One).

Problem

For most of the life of the car (20 years at the time of writing) the temperature readout on the tachometer hasn't worked. While the loss of this unessential feature didn't seem worth fixing to the previous owner (and rightly so), I could hardly call myself an engineer if I wasn't going to have a poke around.

An optional extra for the MINI, the on board computer (OBC) includes automatic MPG calculation, additional controls on the left stalk and some variation of speed and range readouts.

If you're feeling adventurous, OBC retrofit instructions, found on the wayback machine are linked here: 1 & 2. I didn't write them and haven't tried them myself. And while we're at it, this blog post isn't instruction on what to do yourself, simply a log of what worked for me.

Anyway, I don't have the OBC, just the simple temperature gauge.

I got the sense from a few YouTube videos that it was likely to be an issue inside the display module rather than a problem at the other end of the CAN bus. Some people have had success in swapping their modules so I thought it was worth a try. In my case, the LCD is totally blank but some people (see below image) have had weird garbled output, which further suggests a problem local to the display module.

Photo credit: Tony Repairs on YouTube.

First job was to remove the original one and check the part number. This was a nice 5 minute job for my lunch break. I noticed that the original one wasn't sitting flat and that there were gaps between the plastic parts.

Moving on...

Release the steering wheel height adjustment lever.
Drop the wheel into the lowest possible position.
Lock the steering wheel once again.
Undo the two Torx T20 screws behind the tachometer and lift it free.
Unplugging it is very intuitive affair, although I didn't need to do it at this stage.

It was quite clear that a 'mechanic' has had this off already for a look and in the process, mangled the rubber vibration damping sheet and overtightened the screws so as to crush the living daylights out of the plastic.

As if I needed any more reason to do my own servicing.

I got a quote from the local BMW dealer, Dick Lovett. They offered to sell me a new tachometer for £335.84 or fit one for £515.64. Now, as much as I would love to spend half the value of the car on a damn thermometer, I'm not a total moron.

There are a few variations on part number and I'm not certain what all the code details mean.

The part Dick Lovett quoted me for was the 6211-6936294.
The part on my car (2001 MINI One) is 6211-06918356.
I found a replacement on eBay, number 6211-6924924, and the vehicle parts seller assured me it would be compatible:
"As long as you are using this to replace a current rev counter it won’t need re-coding. If your Mini One has never had a rev counter fitted then you would need to code the car so that the electronics know there is now a rev counter."

For £22.99, I've got nothing to loose?

The replacement part also came with the plastic surrounds which, like the tachometer itself, were in mint condition.

After swapping the part (plastic surrounds included) the new one sits perfectly and looks as good as new. Although technically better than new, seeing as "new" for this MINI included some poorly designed electronics.

Oh, and it works!

PCB

For anyone wanting to attempt a repair on their existing module, here is the back side of the broken PCB.