Head unit in a VW
Discussion
2007 Mk5 5 Golf 2.0 GT Tdi. Original radio unit removed and a Pioneer head unit fitted. Bought a fitting kit from Halfords which included the lead to connect it. Put it in and all works perfectly. Until...
If the car is left for a few days and then started, which it does first turn okay, the Pioneer wont turn on. As I didn't know the condition of the battery, not had the car long, fitted a new one (Varta 5 year one). Again all was good for a few weeks then the unit wouldn't turn on. Disconnecting the battery and reconnecting it and the unit started working again.
Stuck with it for around 9 months then the battery disconnect would not work. The only way now which I don't understand at all, is to remove the unit, disconnect the lead from the back of the unit then reconnect and it works again. Thinking it was a faulty unit, I returned it to Halfords who exchanged it for another one, same make and number. Within a few weeks it too went through the same failures.
So, removed it from the Golf and fitted it in my 2010 Caddy which already has a new battery but doing some work on the drive must have dropped the battery voltage as the unit would not switch on. The battery disconnect and reconnect did not work either so had to pull the plug off the back of the unit and it started working again.
I am not an electrician and can only guess that once the battery voltage drops below a value, say 11 volts or whatever, the unit stops working. But why does it need to have the plug removed to make it work again???
If the car is left for a few days and then started, which it does first turn okay, the Pioneer wont turn on. As I didn't know the condition of the battery, not had the car long, fitted a new one (Varta 5 year one). Again all was good for a few weeks then the unit wouldn't turn on. Disconnecting the battery and reconnecting it and the unit started working again.
Stuck with it for around 9 months then the battery disconnect would not work. The only way now which I don't understand at all, is to remove the unit, disconnect the lead from the back of the unit then reconnect and it works again. Thinking it was a faulty unit, I returned it to Halfords who exchanged it for another one, same make and number. Within a few weeks it too went through the same failures.
So, removed it from the Golf and fitted it in my 2010 Caddy which already has a new battery but doing some work on the drive must have dropped the battery voltage as the unit would not switch on. The battery disconnect and reconnect did not work either so had to pull the plug off the back of the unit and it started working again.
I am not an electrician and can only guess that once the battery voltage drops below a value, say 11 volts or whatever, the unit stops working. But why does it need to have the plug removed to make it work again???
They do on the Golf so moved them around. On the Caddy there is no switched live, both wires are permanent live. So, I've found a switched live on the heater control unit and connected there.
The thing is everything works okay for x number of weeks then one day it wont come on. Its like an airbag light that comes on if voltage drops too low and stays on until cleared with a scanner.
Went to the coast yesterday and battery will be fully charged. Mrs took the Caddy this morning and it worked fine.
The thing is everything works okay for x number of weeks then one day it wont come on. Its like an airbag light that comes on if voltage drops too low and stays on until cleared with a scanner.
Went to the coast yesterday and battery will be fully charged. Mrs took the Caddy this morning and it worked fine.
Viper201 said:
12.1v last time (had been putting windows up and down, engine off) then when starting it dropped momentarily to 10.9 before coming up instantly to 14.2.
But the original radios don't go off, that's what confuses me???
12.1 volts is flatter than a flat thing.But the original radios don't go off, that's what confuses me???
You should get around 12.6 on a well charged good battery, 14.2 means the alternator is charging it just fine.
E-bmw said:
Viper201 said:
12.1v last time (had been putting windows up and down, engine off) then when starting it dropped momentarily to 10.9 before coming up instantly to 14.2.
But the original radios don't go off, that's what confuses me???
12.1 volts is flatter than a flat thing.But the original radios don't go off, that's what confuses me???
You should get around 12.6 on a well charged good battery, 14.2 means the alternator is charging it just fine.
Yes, the body control module directs power to the main essentials first then to the other items like the radio. Normally, once the alternator comes online everything returns to normal. This is what I don't understand why the radio wont come on, on its own, once the voltage reaches 12.6 or higher.
Maybe its just a quirk of this Pioneer unit.
Maybe its just a quirk of this Pioneer unit.
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