XJ40 wiring and vacuum

XJ40
1

Hi, My brother bought a RHD 87 XJ40 Daimler. I believe these are equivalent to US spec VDP’s?? Anyway, for various reasons we removed the inlet manifold. Upon refitting we have a few issues that I hope smarter people than I can address.

Firstly, we have a unaccounted for wiring plug. It is located just in front of the Battery (LH Firewall), behind the ABS module and the coolant resevoir. Pics attached. It is round, with 3 wires (Brown/white, Blue/yellow and black. Any ideas what this is please?

Secondly, some vacuum lines. We have a vacuum line that is quite long coming up from a whole bunch of stuff behind the LH headlight. We have nothing connected to the vacuum port on the Cruise control bellow, or connected to the ported vacuum post on the throttle body. The cruise bellows look like they are not meant to have a vacuum connection on this car bit I cant see how it could work without one. Any ideas on what all the guff behind/below the headlight is? Where the vacuum hose form it should go? Any ideas as to what connects to the throttle body please?

some points of interest… this car has only one port on the throttle body…not 2 as many others seem to have… it has never had
an airpump, nor EGR and all its ancillary electrics, so this has nothing to do with this issue.

XJ40 Plug
XJ40 Plug1920×2560 278 KB

XJ40 wiring
XJ40 wiring1920×2560 206 KB

2

I looked on my Australian 92 Daimler at the place you mentioned but the wiring is quite different. There is a connector that leads nowhere but has different wiring. I have never touched it and don’t know why it terminates there. Maybe yours leads nowhere too.

PXL_20220606_232928059
PXL_20220606_2329280591920×1440 269 KB

Behind the LH headlight is a large vacuum canister for the cruise control. A long hose leads to the throttle linkage.

PXL_20220606_233009957
PXL_20220606_2330099571920×1440 275 KB

3

Thanks for tsking the time. Most helpful. Cheers

4

Totally shooting from the hip here but could that connector be for optional front fog lights that are not fitted? I recall reading in the forum of such a connector that in lieu of fog lights should be fitted with a ‘blanking’ (resistor) plug to eliminate the dreaded ‘bulb failure’ warning.

5

I doubt it Mike. I had the bulb failure warning light until I fitted fog lamps to the yellow connectors behind the front bumper, then the warning extinguished.

6

Looks like the ABS module connector to interrogate for DTCs if it in the boot.(DO NOT GROUND/EARTH THE RED WIRE)

Could be the ECM connector to interrogate for DTCs? if it in the front near the bulkhead.