park/safety switch - D2 auto

[phibbzy]

Hi guys,

I have a no start on a 2000 Discovery 2 v8 auto. Starter motor, solenoid, energiser wire, fuse box, relays etc all tested fine through various methods.

Using the nanocom, I can "enable crank" and it starts fine.

Also using the nanocom I can also see the W, X, Y & Z tracks as well as the park/safety switch as the BCU sees it.

I have replaced the XYZ switch with a known good unit.

The park/safety switch issue is intermittent. At first I could remove the XYZ switch, or clock it around slightly on the screws and it would start, run, then when stopped it would not start again - same issue.

I could at one point pull on the wire on the loom and it would engage the park/safety switch on the BCU for a second or two.

I figure there is a brake in the loom for that wire (green on the XYZ and black on the loom) or at least this needs to be investigated further.

Does anyone have any idea where that particular wire tracks through the vehicle and any associated plugs in between? Assuming it ends up at the BCU at some point but which wire on that plug etc?

Bit of a painful one!!!

[Disco W.A]

A common place for trans wiring damage is where it goes over the transfer box.
If you take out the window switch panel there is 2 or 3 plugs under it where the trans harness come through the floor, you should be able to do some continuity test on the harness from there.
Also have a look and feel of the harness above the transfer box

[phibbzy]

A common place for trans wiring damage is where it goes over the transfer box.
If you take out the window switch panel there is 2 or 3 plugs under it where the trans harness come through the floor, you should be able to do some continuity test on the harness from there.
Also have a look and feel of the harness above the transfer box

Yep, got a hold of the RAVE and found the trace color for it. The wire between the plug in the center console (black and green) and the transmission plug is fine, no issue with continuity, however the run between that plug and the BCU is cut somewhere.

Instead of tracking that down, I replaced the run to the plug on the BCU from the center console.

HOWEVER, now the switch is permanently on :confused: allowing the vehicle to be started in P, R, D, N, 1, 2 & 3!

The rave does not indicate there is anything in between this plug and the BCU and that is it supposed to be a straight run... so I am not sure.

[sierrafery]

Maybe there were two complementary issues, unplug that C0681/0668 and check continuity against earth in pin 5(male side) while you select gears... if you get permannent earth unplug the XYZ switch and see then, if you still get earth this way there's a short to earth on that circuit if no earth the problem is within the switch if you se what i mean

as i see you can manage with diagrams so you should be able to figure out why there's permannent earth on that circuit between the XYZ switch and BCU(C0663-11) cos that's why you can start it in all gears , make sure you didnt route a permannent earth by mistake to the BCU park/neutral input

[justinc]

Possibly a bcu fault I have a spare here somewhere if you want to try it?

Jc