Rover 45 battery drain.
Discussion
I have a Rover 45, 1.6 standard car, 54 plate. Recently it has been draining the battery when left idle for, in some cases, 2 days and in others 1 week. The battery is new and has been tested for faults.
Symptoms have included:
battery light staying on, even when started and running
hazard light switch 'clicking' but not flashing, even when car is locked and switched off. In this case, pressing the hazard switch causes only the front lights to flash, press again and only the rear flash, press again and no lights flash but the 'click' continues. During this phase there are no ignition lights when trying to start the car.
battery drained down to 5v overnight, on other nights no loss at all
It's been on fault code readers but nothing shows up.
It can start fine for days on end then not at all unless jumped or put on charge for as little as ten minutes.
Even though it's only had two owners and done 36k, regular service etc I'm at a loss to know wheter to perservere or scrap it. I wouldn't want to try to pass it on with a fault like this.
Any thoughts or advice would be appreciated.
Thanks,
SteveO
Symptoms have included:
battery light staying on, even when started and running
hazard light switch 'clicking' but not flashing, even when car is locked and switched off. In this case, pressing the hazard switch causes only the front lights to flash, press again and only the rear flash, press again and no lights flash but the 'click' continues. During this phase there are no ignition lights when trying to start the car.
battery drained down to 5v overnight, on other nights no loss at all
It's been on fault code readers but nothing shows up.
It can start fine for days on end then not at all unless jumped or put on charge for as little as ten minutes.
Even though it's only had two owners and done 36k, regular service etc I'm at a loss to know wheter to perservere or scrap it. I wouldn't want to try to pass it on with a fault like this.
Any thoughts or advice would be appreciated.
Thanks,
SteveO
Is it the standard radio in it? Maybe someone's spliced into the hazard wiring for an aftermarket one, there are a few sharp edges behind here- maybe chafed wire? Take the fuse out for the hazards and see if it still drains?
Battery light staying on- is it charging while running? Could be a faulty diode in the alternator draining the battery too.
Battery light staying on- is it charging while running? Could be a faulty diode in the alternator draining the battery too.
at 36k-miles it could also be down to lack of use and sitting around too often for too long - it needed and now needs regular use
if the hazards are playing up it could just be a matter of cleaning the crud off the connections to the switch and relay - just taking the connections off and on a few times can be enough to get them clean enough to work - but they still need cleaning properly (a bit of light glass paper ought to do the trick)
disconnect the battery and remove it from the car and fully charge it, a low battery will cause and not help with electrical problems, whereas as a good battery in good condition fully charged will help and it takes a lot of battery power to start a car
take the time to have a look at at this on the battery and starter drain from the great John Twist - http://www.youtube.com/watch?v=_Uk53AYZ_2o
and if you're interested in this on the principles of the alternator - http://www.youtube.com/watch?v=lPmk2FXs_18
and here for where the red light comes in - http://www.youtube.com/watch?v=TMgRfToSiLY
whilst the battery is out off the car you could repeatedly use the hazard switch to perhaps unseize it and clean its internal connections with use - again if you can disconnect one wire at a time from the switch and clean the connections then replace that will help
you can also use spray electrical contact cleaner as a last rinse (or even to help get a switch moving) blow it dry and reconnect using electrical contact grease (or petroleum jelly or coopergrease) to stop future crud build up
make sure all connections are tight
same for hazard relay and connections
with the battery out you can check the plug and connections on the alternator and clean where possible, careful not to cross contaminate or short the wires and connections here with any contact grease, a lot of electric goes from the thicker wires
you can check and clean wires, connections and earths on the light units and bulbs too - cleaning the inside of the lenses in soapy water and wiping the bulbs will help to make them brighter too if they were dirty or misted
rust anywhere will not give a good electrical connection
as said if the red light remains on it could mean as above or perhaps your drive belt is too loose - when the red light is on you're driving on your battery and not recharging it so it will soon go low
all connections and wires should be clean secure and protected
ETA:
"It's been on fault code readers but nothing shows up."
- you trust computers 
finally, if someone has interfered with the wiring at any stage then all bets are off
if the hazards are playing up it could just be a matter of cleaning the crud off the connections to the switch and relay - just taking the connections off and on a few times can be enough to get them clean enough to work - but they still need cleaning properly (a bit of light glass paper ought to do the trick)
disconnect the battery and remove it from the car and fully charge it, a low battery will cause and not help with electrical problems, whereas as a good battery in good condition fully charged will help and it takes a lot of battery power to start a car
take the time to have a look at at this on the battery and starter drain from the great John Twist - http://www.youtube.com/watch?v=_Uk53AYZ_2o
and if you're interested in this on the principles of the alternator - http://www.youtube.com/watch?v=lPmk2FXs_18
and here for where the red light comes in - http://www.youtube.com/watch?v=TMgRfToSiLY
whilst the battery is out off the car you could repeatedly use the hazard switch to perhaps unseize it and clean its internal connections with use - again if you can disconnect one wire at a time from the switch and clean the connections then replace that will help
you can also use spray electrical contact cleaner as a last rinse (or even to help get a switch moving) blow it dry and reconnect using electrical contact grease (or petroleum jelly or coopergrease) to stop future crud build up
make sure all connections are tight
same for hazard relay and connections
with the battery out you can check the plug and connections on the alternator and clean where possible, careful not to cross contaminate or short the wires and connections here with any contact grease, a lot of electric goes from the thicker wires
you can check and clean wires, connections and earths on the light units and bulbs too - cleaning the inside of the lenses in soapy water and wiping the bulbs will help to make them brighter too if they were dirty or misted
rust anywhere will not give a good electrical connection
as said if the red light remains on it could mean as above or perhaps your drive belt is too loose - when the red light is on you're driving on your battery and not recharging it so it will soon go low
all connections and wires should be clean secure and protected
ETA:
"It's been on fault code readers but nothing shows up."
- you trust computers finally, if someone has interfered with the wiring at any stage then all bets are off
Edited by nta16 on Sunday 22 September 01:58
54 plate? So the facelift with the rear number plate on the rear bumper and the electronic boot release? (three button fob?)
If so, almost certainly Body Control Unit: http://www.ebay.co.uk/gds/MG-Rover-Pektron-SCU-BCU...
Basically, they're s
t, and go wrong all of the time.
If so, almost certainly Body Control Unit: http://www.ebay.co.uk/gds/MG-Rover-Pektron-SCU-BCU...
Basically, they're s
t, and go wrong all of the time.Gassing Station | MG | Top of Page | What's New | My Stuff