ABS pump and sensor testing

[larkin 0]

Hi there guys,

bit of background:

My ABS light is always on

 

I Vag-Com'd and get the following error on the ABS:

00276 - ABS Outlet Valve: Left Rear (N136)

35-00 - -

 

So it seems the pump may be broken as the valves are internal to do with solenoids in the pump I gather

so I am sourcing a new pump/valve unit which I am waiting to get..

 

meanwhile I popped out the ecu today and checked the connections, there was a small bit of white oxidation on a couple of pins but when I took apart the ecu all the internals looked clean and dry (the motherboard was like new inside) I sanded the connectors, sprayed some electrical solvent and plugged it back in - no change in error codes

 

While I had the ecu out I checked the resistance of the 4 sensors by checking the relevent pins on the loom, the 2 back ones seem fine as they have a resistance within the bounds (1.02, 1.04 ohms), the 2 front ones however have a reading of 1.

 

I also checked the inlet and outlet valve resistances from the relevant abs ecu loom pins and they also confirm the error codes (i.e the 4 inlet valves and 3 outlet valves show the correct resistance (3-10ohms) but the left rear shows a resistance of 1

 

(got the multimeter test procedures off of Autodata, can post em if they are any hep to anyone else)

 

My Conclusion:

The 2 front sensors need to be cleaned/replaced

The pump needs to be replaced unless theres another way of fixing the outlet valve

 

Just wondering if there is any other way to fix the left rear outlet valve error without changing the pump?

I have changed the brake fluid, and tried the hammer tap approach :wink:

[gollfy 0]

Dont think there is anyway of changing the valves as I think its a sealed unit. I would advise swopping the pump first before bothering with the sensor's. Should be able to pick up a cheap pump for around £20ish 8) (ebay etc)