whats my plug

[woody]

i had to replace my brake light switch yesterday on y disco 1 (1998)
i removed a piece of black trim from above the pedals to change the switch
and i noticed a plug (or socket) in the panel
what is the plug for as my first thought was its a diagnostic test point
but i didnt think there was any on my model

[Disco Matt]

The later 300TDIs did have "fly by wire" throttles and other electronic gubbins. The puzzling part is that mine (an all-mechanical 1996 model) has that plug too!  :-k

[stageonesimmo]

Its the OBD (On Board Diagnostics) socket and is used to plug into the ABS or EGR, also shorting out various pins on it makes the fault codes flash up at the warning lamp (well, for ABS anyway). You may find it's replaced the ABS diagnostic plug (blue coloured, 3 pin) that gets mentioned loads in ABS fault threads - it explains why after months of searching on mine (also a '96 (XS) 300 TDi), i couldnt find the blue plug to check my fault codes and had to resort to paperclips in various holes in the OBD socket................

I'm sure a search for 'OBD' on here will bring some more stuff up................

[woody]

on my disco there is no ABS
and the pump is controlled by a cable?????
whats left to diagnose????

[stageonesimmo]

The EGR.

Plus, the looms are often common items that are fitted to all vehicles regardelss of spec and then things are just plugged in to bring it to the spec required, makes things easier at assembly.  So even though you may not have much stuff to diagnose plugged into the loom, the OBD connector is there anyway as its a common loom.........

[woody]

The EGR.

Plus, the looms are often common items that are fitted to all vehicles regardelss of spec and then things are just plugged in to bring it to the spec required, makes things easier at assembly.  So even though you may not have much stuff to diagnose plugged into the loom, the OBD connector is there anyway as its a common loom.........

cheers for that

EGR is blanked off