urgent help !

hi fellas need a bit of urgent help. Wife got back from a day out turned the disco off (disco 1 300tdi) and a very loud buzzing coming from the engine bay! Its coming from whatever is at the back of the air filter between that and the washer bottle, large block of ally with pipes in! sorry don't know what it its called disconnected the power and its stopped help!!!

That will be the ABS modulator then, and as it is part of the braking system you should ask an LR garage to look at it and give an opinion asap.

Yeah just looked and its the modulator your right. Whys it buzzing when the ignition is off?

Relay stuck??

is the relay on the unit itself? Now i have unpluged it and plugged it back in it's stopped. (apparently the abs light was on on the journey back home) hoping for an easy fix really, don't like going to the stealers! cos im a tight arse and i like to know i can fix things for myself.

Which ABS relay? there are three and located behind the front pasehger kick panel'

Copied from the LR workshop manual

If a fault has occurred, or has been identified by ECU
self diagnostic function and ABS warning light is
illuminated. The system and components must be
checked to locate and rectify fault, using Testbook
diagnostics.
NOTE: If warning lamp has indicated a
fault in system, and no fault code has been
stored in memory, cause of fault is:
a) Failure in electrical supply
b) Bad ECU ground
c) Faulty warning light relay
d) ECU not connected
Before commencing fault diagnosis procedure
following items must be checked:
1. Inspect all exposed cables for damage or
abrasion.
2. Check ground on ABS system.
3. Battery - state of charge.
4. Check hub end-float.
5. All ABS fuses and electrical connections.

looks like another greasy weekend coming up. If its not the relays causing it to stick and hum any other ideas?

On a 300 the abs can be checked manually. You need to remove the relay, bridge a pair of wires in the data link and the dash will flash a fault code. I'm sure some one on here will be able to tell you which wires to bridge but if not PM me and I will look it up for ya.

andyoak said:

On a 300 the abs can be checked manually. You need to remove the relay, bridge a pair of wires in the data link and the dash will flash a fault code. I'm sure some one on here will be able to tell you which wires to bridge but if not PM me and I will look it up for ya.

Click to expand...

thanks for the help, can you tell me where the relay is? and which ones to bridge? I went for a spin today and it was fine no buzzing or abs light

you need to first remove the warning lamp relay [underdash n/s near abs ecu with a shed load more] then bridge pins 4 and 15 in the data link plug. Light will then flash the fault codes. Remove the bridge to while it's flashing to clear the code. If the light is now out i would think that what ever was causing the problem has sortted it's self out.

thanks for that i'll give it a bash at the weekend