Charge & Hand brake lighs come on while driving

[dazza300zx]

Hello all
I have a 2007 R51 6sp man desiel,every now and then the Charge & Hand brake lights come on while driving if i let the revs drop back to idle they go out but come back on when I eccellrate back up.if i pull over turn off the engine take the key out lock the dooors then unlock them put the key back in and start the car it's back to normal un till it does it again ,has anyone else had this problem ?? and if anyone what causes it.
Thanks....Darren

[smj999smj]

Sounds like you have a charging system issue, possibly a bad alternator. You'll need to have it checked to be sure. Due to the nature of your problem, make sure it's checked not only at idle, but also at increased RPM, as well. I used to have a cheap voltmeter that plugged into the power socket (or lighter socket, as it used to be called) that came in handy as you could check your charging voltage while driving.

[dazza300zx]

if it was a battey problem why does reseting the key make them go out?.

[smj999smj]

System could be overcharging as you accellerate and the engine revs increase. If you stop and cycle the key, the cluster runs a bulb check. Start the car and the charging voltage may be fine but as you accellerate, the overcharge causes the lights to come back on. This is one possible scenario...bottom line, any time you see the charging system light come on you should do a proper charging system test.