R129 speedo issue
R129 speedo issue
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Discussion

Sid123

Original Poster:

270 posts

201 months

Saturday 26th December 2015
quotequote all
Happy Christmas everyone!
Apologies if there are loads of links to this issue but perhaps someone can help.
1997 SL280 5 spd auto
Speedo can go mad and crank itself round to 160.
Usually goes back to zero if you switch off and on again (90% of the time) but not always.
Sometimes it might take 3 on and offs...
Hoping it would solve the problem I have just had the NSF wheel speed sensor replaced at Merc for £192 but has made no difference.
Having read a bit of stuff online, and what Merc told me, it is suggested that if the wheel speed sensor was not the issue then it's the instrument cluster.

In people's experience if it's not the wheel speed sensor is the next only option the instrument cluster or is there something simpler or cheaper that might be the cause?
Sometimes the speedo works fine for days and other times after 5 mins it goes mad.
Any suggestions?
Thanks.
Sid

Edited by Sid123 on Tuesday 29th December 10:03