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Ive had a warning light come on the dash/Speedo for light bulbs so checked and it seemed i had 2 bulbs on the rear driver side door had gone, anyway went out to the car this evening to see they were working fine Yesterday the esp light came on then reset its self the next day and also my secondary air pump is not getting any power ive pulled this code. P1602 Power supply terminal 30: Voltage too low: yeh and also the speckers are on making a hising sound wen i first unlock the car but goes off after about a minute ??


So any help will be good maybe its the battery but think i had a new one about 3 years ago!!

If you put a voltmeter on the battery what reading do you get with the car switched off and then with the car running. I'd expect around 12 volts with the car off and around 13.8 volts when running. If they both check out then your battery and alternator are probably both OK.

May also be worth checking how well the battery holds up when under load. Measure it with everything switched off and then put your headlights on and see if the voltage falls indicating that the battery hasn't held much charge.

MarkPRS6 wrote:If you put a voltmeter on the battery what reading do you get with the car switched off and then with the car running. I'd expect around 12 volts with the car off and around 13.8 volts when running. If they both check out then your battery and alternator are probably both OK.

May also be worth checking how well the battery holds up when under load. Measure it with everything switched off and then put your headlights on and see if the voltage falls indicating that the battery hasn't held much charge.

Hi thanks for the reply ive just checked the battery and wen the car is off its at 12.37-12.38 and wen the car is switched on under load the charge is 13.46 and keeps goin up slightly so is charging and this is with everything switched on in the car so think the battery is ok ?

And with the engine running not with anything on its at 13.83 and rising