ABS Sender Testing

davidbooker · 27th March 2021, 12:02

Hi
My abs light came on the other day, after flashing on and off for a couple of weeks. The AA diagnosed the rear offside sender as the culprit, so I bought a new one on Ebay. The garage fitted it yesterday, and it seemed to work. However, on the short drive home, the light came on again. Before I return to the garage (he knows it's on again) is there any way of testing the continuity of the sender with a multimeter? It's possible the new one is a dud, as it seemed to cure the problem for about 300 yards!
Many thanks.

Arctic · 27th March 2021, 13:00

Quote:

Originally Posted by davidbooker

Hi
My abs light came on the other day, after flashing on and off for a couple of weeks. The AA diagnosed the rear offside sender as the culprit, so I bought a new one on Ebay. The garage fitted it yesterday, and it seemed to work. However, on the short drive home, the light came on again. Before I return to the garage (he knows it's on again) is there any way of testing the continuity of the sender with a multimeter? It's possible the new one is a dud, as it seemed to cure the problem for about 300 yards!
Many thanks.

Hi David.
Yes it can be tested if you make up a ABS loom or ask the club if you can borrow one of theirs, they should have two.
https://the75andztclub.co.uk/forum/s...d.php?t=260420

I think you will most likely find its the bearing and the magnet which is built in, most likely rust debris from the back plate.

1

2

Earth the meter.

3

Turn the wheel and readings are as below.

4

5

Lower the back seat and join the ABS tester loom to check.

6

7

My money is still on the bearing

rab60bit · 28th March 2021, 15:38

Quote:

Originally Posted by davidbooker

Hi
My abs light came on the other day, after flashing on and off for a couple of weeks. The AA diagnosed the rear offside sender as the culprit, so I bought a new one on Ebay. The garage fitted it yesterday, and it seemed to work. However, on the short drive home, the light came on again. Before I return to the garage (he knows it's on again) is there any way of testing the continuity of the sender with a multimeter? It's possible the new one is a dud, as it seemed to cure the problem for about 300 yards!
Many thanks.

Had a similar issue a few months back but I hadn't had a diagnostic check. After fiddling with an elimination process using known good sensors I gave up and just replaced both rear bearings (not a big diy job and relatively modest OEM parts cost - problem solved and hopefully no issues with rear wheel bearings (the originals had covered in excess of 165K) for the rest of her life.
There is a very thorough explanation of the ABS system somewhere on here that points to the O/S/R bearing as the most probable culprit - trouble is I didn't read it first

davidbooker · 28th March 2021, 17:28

Many thanks for all your advice - food for thought! 👍

27th March 2021, 12:02	#1
davidbooker Gets stuck in '51 Rover 75 2.5 V6 Conn. Purchased 02/05 Join Date: Dec 2006 Location: Whitby Posts: 571 Thanks: 8 Thanked 33 Times in 22 Posts	ABS Sender Testing Hi My abs light came on the other day, after flashing on and off for a couple of weeks. The AA diagnosed the rear offside sender as the culprit, so I bought a new one on Ebay. The garage fitted it yesterday, and it seemed to work. However, on the short drive home, the light came on again. Before I return to the garage (he knows it's on again) is there any way of testing the continuity of the sender with a multimeter? It's possible the new one is a dud, as it seemed to cure the problem for about 300 yards! Many thanks.

28th March 2021, 17:28	#4
davidbooker Gets stuck in '51 Rover 75 2.5 V6 Conn. Purchased 02/05 Join Date: Dec 2006 Location: Whitby Posts: 571 Thanks: 8 Thanked 33 Times in 22 Posts	Many thanks for all your advice - food for thought! 👍