My VW Golf mk2 is draining its battery!?
Answers:
if its not the alternator, check all the earth straps. usuall the one onto the side of the gearbox is a pain. also the front light wiring loom is prone to short circuits resulting in a dead battery, this happened to me. check the alternator first. put a volt meter across the battery terminals. check its reading around 11v, when you rev the engine, this should rise to around 13v. good luck. any more probs, just ask me. i know mk1s & mk2s inside out.
You need a new alternator. A bad altenator will drain your battery
it sounds like your alterantor is playing up! it charges the battery when you are driving.
it could be the boot lamp staying on,don't open the boot,pull the rear seat forward,to see if it stays on,that's when a charged battery is fitted of course,remove the bulb is the simple answer if its staying on,if its the alternator you will find the radio goes off the wipers will go slow & the engine will cut out when you are driving.
frist put in a charged battery, as mentioned check voltage with engine running should be 13.5 - 14.5 volts if not then its the alternator or wiring to it. second disconnect the ground terminal and put a test lamp between ground terminal and the ground post on battery - if it lights up then there is a draw - if u have done it correctly its easily verifiable just open the car door or turn on the headlight switch (the bulb will light then go off when u close door or turn off switch). if the bulb lights dim its a small draw - maybe memory or alarm (flashes dim) if the bulb is bright then find the fuse/relay box under hood and remove 1 fuse at a time untill the light goes out - this gives u the circuit the draw is on. put fuse or relay back in (light on) then got to the inside fuse box to further narrow your search to a specific circuit. from here u will need a wiring diagram of car to see what else is on circuit you will have to check (ex. the cigar fuse can run radio, power outlets vanity mirror lights ect. as well) hopefully it just the alternator. (p.s. the cheapest test light is a 194 bulb found in most parking lamp or license plate light socket)
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