parked car up (outside) around two weeks ago ,went to start it and battery was flat so jumped it off with booster pack , but now abs light is on wasnt before i parked it up.
any ideas
abs light
Moderator: martauto
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Brianmoooore
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Booster packs are a menace!!
You almost certainly have an early type ABS system, which has an overvoltage protection circuit to protect the ABS ECU from voltage surges. The device is a rectangular silver box, slightly smaller than a pack of cards, that is clipped to metalwork to the right of the ABS ECU.
Besides a relay, which switches the ABS on with the ignition, the device contains a non replaceable fuse, which will have blown, and a zener diode, which may or may not have blown.
You almost certainly have an early type ABS system, which has an overvoltage protection circuit to protect the ABS ECU from voltage surges. The device is a rectangular silver box, slightly smaller than a pack of cards, that is clipped to metalwork to the right of the ABS ECU.
Besides a relay, which switches the ABS on with the ignition, the device contains a non replaceable fuse, which will have blown, and a zener diode, which may or may not have blown.
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Brianmoooore
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No, thats the ABS ECU itself.
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Brianmoooore
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Unofficially, as long as the zener diode in the unit is OK, you can open it up, solder a shorting link in place of the failed fuse, and instal a 8 amp fuse in the red wire from it.
From around 1989, the power feed arrangements to the ABS system were changed, and the overvoltage 'relay' deleted. These later ABS ECUs do not have any overvoltage protection, but AFAIK, there's no way of identifying these later units, and I don't know if there is actually any difference in them from the earlier ones. It's possible that improvements in semiconductor technology during the production run rendered the protection unneccesary on later production, or it may have been decided that it wasn't needed anyway.
From around 1989, the power feed arrangements to the ABS system were changed, and the overvoltage 'relay' deleted. These later ABS ECUs do not have any overvoltage protection, but AFAIK, there's no way of identifying these later units, and I don't know if there is actually any difference in them from the earlier ones. It's possible that improvements in semiconductor technology during the production run rendered the protection unneccesary on later production, or it may have been decided that it wasn't needed anyway.
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Brianmoooore
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Above post was written before I saw your last post!
Unit is silver, somewhat smaller than a pack of cards, and mounts to the right of the ECU, on the same bracket, IIRC.
Unit is silver, somewhat smaller than a pack of cards, and mounts to the right of the ECU, on the same bracket, IIRC.
Sorry to jump on this, but seeing as your sorted mate...
I have a 1989 (Tech 2 Sport) and have the same problem, the light stays solid through cranking and starting. Read in the Wiki page about earlier and later cars and their relevant relay locations - would mine be a later one I take it (being a Tech 2)? So my relay would be on the pump itself? Is there another one? Where would that be located?
And where is the best place to buy replacements from?
Thanks in advance,
I have a 1989 (Tech 2 Sport) and have the same problem, the light stays solid through cranking and starting. Read in the Wiki page about earlier and later cars and their relevant relay locations - would mine be a later one I take it (being a Tech 2)? So my relay would be on the pump itself? Is there another one? Where would that be located?
And where is the best place to buy replacements from?
Thanks in advance,
not sure if yours will be the same as mine ,but mine is a 1990 325 se , easy to check ,remove glovebox straps undo one self tapper and two thumb screw off plastic cover in top of glove box ,you will see the big abs ecu and if yours is an early one like mine just to the right an aluminium relay unit clipped to the frame work(sits above the framework ) cant miss it.Due to me being an elctrician for 27 years i know a strand from 0.75mm flexible cable (most power cords to tv's ect) is rated @ 5 amps so just re soldered one of these across the melted fusable link inside the relay.
cheers dav
cheers dav