You might need to get someone to hook up a workshop diagnostic tool to it. If you can find a bluetooth OBD ELM327 adapter and get the Android app Torque to it you will get the answer, otherwise it's a workshop tool. Lubemobile have these and you can always call them and ask how much they'd charge to stop and get any codes from the ECU. But ... that might not be necessary.
Which dial is flickering? The instrument cluster? That could be:
- Bad battery. Try another vehicle battery - the V9X uses lots of amps to turn the engine over so don't use a battery out of a little car.
- Bad earth on the instrument panel. Usually shared with the stereo and often plays up if the stereo is removed.
Was the engine running before? Did it exhibit any odd symptoms, loud noises, did it stop suddenly?
What happens if you turn the key to 'start' ?
If the engine turns over, can you smell diesel in the exhaust?