Hi! First post of many as I overhaul my 04 Disco.

This one has boggled my mind all day.

I set about removing an old analogue tachograph that I’d been meaning to get rid of as it’s unsightly and had a mess of wires hanging out.

Traced everything, unplugged it all and found two total wires spliced into the Disco’s own electrics.

One up in the instrument panel (assume for speedo data) and then one into what I think is a power supply under the right-hand side panel (driver side on rhd vehicle). I’ll need to check the manual but it’s a slightly thick brown cable.

Clipped these, cleaned and sealed the gaps left by the splices, easy peasy - or so I thought.

Went to lock the vehicle after tidying up and locks won’t activate. Check the ignition light and it’s off. No power at all anywhere.

Is it possible the tacho was installed in such a way as to create a new circuit, and removing it broke that? I traced everything and was sure it was fully independent.

 

Was the battery connected? If so -- I bet you blew a fusible link underhood. Give it a check.

 

You're partially right, blimey I thought this would be a tough one but she's all up and running now.

Mixture of bad wiring and not disconnecting the battery for what I thought would be a quick easy removal.

• Checked and found nothing blown (thankfully)
• Convinced something further along the chain must then be shorting out
• Checked every. single. wire. under the driver side
• Found a loose ground that on inspection, had just been tied around a grounding screw and must have 'fallen off' whilst I was tracing and removing the other wires
• Temporarily re-attached it, turned ignition, full electrical reset, remove key, re-insert and turn again and engine starts up like a charm

Happy ending for now, fingers crossed speedo and odo all work fine, that'll be the next test. There's a lot of messy splices for accessories in this vehicle, probably going to have the same pains going through and removing / repairing it all...

Is there anything I should be checking / looking out for on a full electrical reset? I believe odo and temp will have changed units?