So, rear rocker cover gasket was replaced this morning at a dealership.
Plenum removed, gasket replaced, plenum replaced.

Happily drove normally after that for about 15 k's, parked it, return about 6 hours later and it wont start. Co-incidence?

Symptoms are intermittent weak flashing of dash lights when key turned, no turnover, no click sound. Headlights are very dim, radio resetting itself and wanting code input, door locks weak, internal reading lamp weak and flashing.

I'm thinking battery. Battery has an indicator on it that shows good, (green indicator).
Dont know the history of the battery. Date stamp label is torn, but only seems to go up to 2010.

Check that the terminals are tight. Dealer may have disconnected the battery.

Check the battery. Dealer may have swapped batteries on you. (Joke, by the way - I hope.)

New battery time, I think.

Terminals are tight. Yeah, i assume battery died co-incidentally same day! Organising a new one ...

check the wiring harness that runs along the plenum isn't caught between the plenum and the intake. (looking at the engine it sits on the right hand side corner of the plenum)

check the wiring harness that runs along the plenum isn't caught between the plenum and the intake. (looking at the engine it sits on the right hand side corner of the plenum)
I'll check it, but pretty certain its the battery.
New battery is in, thanks to RACV. Old battery tested bad. Car started up fine. Set the trip computer, did the engagement learning procedure, all good, drove out of the car park, down the road to go home, checked my speed, -45kmh, checked the mirrors ... wait a sec ... -45kmh?!
:roflwtf: The speedo is broken now?

The needle is pointing straight down, somewhere between 0 and 240kmh.
To do that it must have turned fully clockwise, cos theres a stop just before zero it couldnt have gotten past.

Anyone know whats happened? :shock:

Only suggestions i have so far are to try disconnecting the battery again and also checking for any blown fuses.
These seem unlikely to me, but worth a try. Otherwise i think i'll have to remove the black out cluster and take it to someone who can repair it.

Can anyone tell me where the sensor/connector is in the engine bay, i should check that too in case its not properly connected or something.

I'll check it, but pretty certain its the battery.
New battery is in, thanks to RACV. Old battery tested bad. Car started up fine. Set the trip computer, did the engagement learning procedure, all good, drove out of the car park, down the road to go home, checked my speed, -45kmh, checked the mirrors ... wait a sec ... -45kmh?!
:roflwtf: The speedo is broken now?

The needle is pointing straight down, somewhere between 0 and 240kmh.
To do that it must have turned fully clockwise, cos theres a stop just before zero it couldnt have gotten past.

Anyone know whats happened? :shock:

I can tell you exactly what happened.
While working on the car, the mechanic shorted a live wire, probably when loosening the alternator. This sent a spike through and the needle on the cluster has now gone over to the other side.
You need to take out your cluster, remove the clear cover, and carefully push the needle (not with your fingers) back to zero. There is no resistance and the needle will go back into position easily. Then replace everything and you are good to go.

Same thing happened when someone was working on my car. Grrrrr.

P.S. I still haven't disposed of the mechanics body for doing this to my car.

Vehicle speed sensor is on the transmission. You might need to remove intake snorkel to see it.

I can tell you exactly what happened.
While working on the car, the mechanic shorted a live wire, probably when loosening the alternator. This sent a spike through and the needle on the cluster has now gone over to the other side.
A spike may be the root cause, but it wasnt the mechanic. I drove the car after they completed the job and it was fine. Speedo worked normally. Must have happened when i turned the key and found the battery was flat. Its a weird co-incidence that battery died same day.


You need to take out your cluster, remove the clear cover, and carefully push the needle (not with your fingers) back to zero. There is no resistance and the needle will go back into position easily. Then replace everything and you are good to go.

Same thing happened when someone was working on my car. Grrrrr.
Wow, i hope thats all thats required! But that needle is not moving at all when driving, so its not obvious how that works.

Check the earth wires on the engine and engine to body. I've seen this before where an earth was loose/disconnected and it caused the dials to go crazy and no start

I can tell you exactly what happened..
Thank you GTVi, you were absolutely right, that was exactly the problem. :)
Turned the needle back and its back to normal.
I checked calibration too (using the speed alert and my GPS) and its fine.

Couple of tips for anyone needing to remove the cluster;
First, do yourself a big favour and remove the steering column shroud first. I didnt and had a job to manouver the cluster surround out over it. Too tight.
Secondly, there is some kind of insulation covering the cables at the rear which is aged, sticky and crumbly. Dont touch it if u can cos it sticks to your fingers and then gets all over the clear cluster shield. Cleaning it was a pita.

Although issue fixed a few corrections for those wanting correct info

For starters, there is no speedo drive gear on the L and W series, they use the output shaft sensor for the speedo

Secondly, I have no idea why on earth someone would take off the alt to do a rocker cover gasket, I would be going back to that dealer and asking some serious questions even though the issue is now fixed

To remove the cluster is easy when the steering wheel is set at its lowest setting without taking off the shroud

..Secondly, I have no idea why on earth someone would take off the alt to do a rocker cover gasket, I would be going back to that dealer and asking some serious questions even though the issue is now fixed
Yeah, that didnt happen. I dont know why GTVi said that, maybe he was thinking about whatever caused his speedo needle to swing around? In my humble opinion this was caused by some kind of spike when my battery died and i tried to start it.
Battery was "shorted" according to the RACV guy.

..To remove the cluster is easy when the steering wheel is set at its lowest setting without taking off the shroud
Lowered the wheel fully and locked it. It was still a tad tight though and i had to be extra careful not to scratch anything which made it difficult.