9 replies to this topic

[SimonM]

Hi,

 

Probably a stupid question but  I don't want to damage anything. My ABS light is on and the speedo behaving erratically. I suspect its the connection to the hub but thought I'd check the fuses first - in particular 22. Browsing through the site I see that it might also be useful to remove Fuse 8 for a few minutes to see if a reset may help but wasn't sure whether I should do this with just the ignition switched on or the engine actually running, or whether it doesn't make any difference.

 

Thanks

[Kieran McC]

Check the hub wires , reset the abs with a Opcom

[techieboy]

Don't bother removing the fuse, it won't clear an ABS fault as the fault is stored in a different ECU to the main engine ECU.

[SimonM]

Thanks - but does this mean that an Opcom won't be able to reset the ABS then as I thought it connected straight to the main engine ECU?

[techieboy]

No, Op-Com can talk to the ABS ECU as it uses a correctly wired OBD interface that communicates over the separate pin in the OBD socket that the ABS ECU is connected to.

[peteslag]

I had this on my old turbo. It was the connector on the rear left hub. Nice easy fix.

[Zoobeef]

Fuse 8 is the engine ECU fuse. Only ever pull it with the ignition off. This will reset engine codes and fuel trim learning. Abs ecu is separate and can be read through the same obd port using op-com. You can reset faults with op-com although when you fix the fault the light will go off after a short drive anyway. Using op-com will tell you where the fault is though. But, as your speedo is playing up, it is pointing towards your nearside rear hub as the speedo signal is taken from that hubs abs signal. Check the wires and connector going too that hub as they get brittle.

[SimonM]

Thanks all; I suspect it is the connector as you suggest and I'll have a look at that. Just out of interest, though, how can pulling the fuse with the ignition off reset anything if no current is flowing? Or once the fuse is removed, then do you switch the ignition back on?

[Zoobeef]

Fuse 8 connects the battery to the ecu directly regardless of the key position.

[SimonM]

Thanks!