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Discussion Starter #1
Hi, I know this issue has been raised before but I never found out how, or if it was resolved.

My ZR 160 has ABS - The speedo does not work

I have replaced the transducer in the gearbox and the F/R and L/R ABS sensors
I secured the "loose" FR reluctor ring - which was also out of position (found when replacing the sensor)
The ABS warning light illuminates and goes out at startup. It has not illuminated at any other time.
When connected to my diagnostics I can get a speed output on screen so I know the gearbox transducer is working.

My first question is have I changed the correct ABS Sensors..
Could the ABS ecu be the issue, how can I tell if it is?
What other avenue will provide the feed to the speedo

Please bear in mind I am in Canada and there are no other ZR's here.
My spares and replacements (new and used) have to come from the UK
Your input and suggestions would be welcomed
 

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'06 MG ZR +120 (HQM) '04 MG ZR 105 (IAB)
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I think the speedo on your 160 should take its signal from the ABS ecu? There is an MG Rover technical bulletin which gives the transducer being deleted from ABS equipped smaller engined cars (R65 gearbox) from 12th July 2002 and the signal taken from the ABS ecu. The 1.8 engined ZRs (PG1 gearbox) always had ABS, I may be wrong, but I had assumed that they had always taken the signal from the ABS system rather than the gearbox?

On all models of 25/ZR, regardless of engine or braking system, the engine ecu takes a speed signal from the front left ABS sensor which is used as a 'rough road speed sensor'. This signal has no relevance to the speedometer reading at all.
If you are getting a road speed reading from your diagnostic reader (as opposed to the 'rough road' speed signal), I would think the most likely fault is either a damaged wire or bad connection in the feed to the speedo, or possibly a fault in the speedo itself. If it is a faulty speedo, it might be worth having a look at eBay for a used ZR instrument binnacle, but beware that these are engine/braking system specific, so you will need a set from a petrol car that had ABS (they are clearly marked as such on the back of the unit). You will probably also need one specifically from a 160 as the red line on the rev counter is higher than for the 105 or 120 models, unless you just swap the speedo across.

Interesting that you have a ZR in Canada - it isn't completely alone as there is another Canadian member of the forum who has a Rover 25 over there :)
 

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I agree with MITC, sounds like the speedo unit or it’s feed. Can you get a speed output from the speedo connections? If so, a breakers that will post or check Rimmers...
 

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Discussion Starter #5
I think the speedo on your 160 should take its signal from the ABS ecu? There is an MG Rover technical bulletin which gives the transducer being deleted from ABS equipped smaller engined cars (R65 gearbox) from 12th July 2002 and the signal taken from the ABS ecu. The 1.8 engined ZRs (PG1 gearbox) always had ABS, I may be wrong, but I had assumed that they had always taken the signal from the ABS system rather than the gearbox?

On all models of 25/ZR, regardless of engine or braking system, the engine ecu takes a speed signal from the front left ABS sensor which is used as a 'rough road speed sensor'. This signal has no relevance to the speedometer reading at all.
If you are getting a road speed reading from your diagnostic reader (as opposed to the 'rough road' speed signal), I would think the most likely fault is either a damaged wire or bad connection in the feed to the speedo, or possibly a fault in the speedo itself. If it is a faulty speedo, it might be worth having a look at eBay for a used ZR instrument binnacle, but beware that these are engine/braking system specific, so you will need a set from a petrol car that had ABS (they are clearly marked as such on the back of the unit). You will probably also need one specifically from a 160 as the red line on the rev counter is higher than for the 105 or 120 models, unless you just swap the speedo across.

Interesting that you have a ZR in Canada - it isn't completely alone as there is another Canadian member of the forum who has a Rover 25 over there :)
I am aware of the 25 which is out east and I have a 200 bubble also, but this is the only ZR160 nere
 
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