Dashboard n wipers gone after battery went flat

[Beautdriver]

Standard thing is to check fuses and relays.
Next, disconnect the battery for 30 minutes.
When battery is reconnected, turn ignition to 'on', do not crank, let the electronics do their start up self checks.
See if the IQ and the other systems return to normal.

Hi just want to update that it's all been fixed, very easily. Your comment Imoengr is the closest to what actually worked. I firstly took it to the people who usually service my friend's car. He fixed the wipers by turning on the engine and manually pushing the wipers down - he could hear a slight whirring noise which meant the wipers had just got stuck in the moment. So that was easily fixed, and not necessarily related to the battery. He didn't know how to fix the radio however, and suggested I may need a totally new one. A friend had recommended another service station, so I went there, and they said they could not reprogramme the radio without the code. They said I needed to get the code from the local Commodore dealership, Geissler Motors in Goulburn. I went there, and the front reception said it would cost $45 to get the radio code for that model. Then luckily Brady walked past, the expert in commodore electronics. He unplugged the negative from the battery, and then replugged it, and the radio came back on instantly. All in all it took around 2 minutes.

so for the record, disconnecting the battery negative charge, can sometimes reset the radio if it's gone dead from a flat battery!! So relieved. And thanks for the help of this forum, you got it all started. And massive praise to Brady the Commodore whizz. Cheers )

 

[Skylarking]

If you still have issues after disconnecting testing and reconnecting the battery, I’d check all fuses…

If the battery load tests ok and the charging circuit tests ok and all fuses are ok and you’ve disconnected the battery waited 10 minutes and reconnected the battery to cold reboot the car, and the faults still exist, then we need more info …

 

[Beautdriver]

Actually Skylarking you were right on the money early up. A cold reboot after disconnecting the battery worked immediately. The radio came to life. The mechanic explained to me the car is running all these "apps" in the background that can cause rapid battery drain, similar to a smart phone.

I'm surprised though that a powerful car can be brought down by something so basic! My 2002 manual Toyota Hilux doesn't have this issue

 

[Skylarking]

I'm surprised though that a powerful car can be brought down by something so basic! My 2002 manual Toyota Hilux doesn't have this issue

I’ve read that a infotainment/GPS fault that results in loss of date/time can result in some Mercs not being able to be started

Due to a infotainment/gps fault, not having radio or navigation I can accept but to not be able to start the car is just bonkers

 

[Beautdriver]

I’ve read that a infotainment/GPS fault that results in loss of date/time can r3ailt in some Mercs not being able to be started

Due to a infotainment/gps fault, not having radio or navigation I can accept but to not be able to start the car is just bonkers

Yeah 100% definate design flaw/ archilles heel