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[Andy663]

What's an HRW relay? Could this be causing my battery to go flat?

[0795omega]

heated rear window,dont know how that could make battery go flat?

[Andy663]

I took the car out this morning and did 4 short runs of approx 2 miles per run, over 2 hours. 3 hours later the battery was almost dead. I've been reading some posts concerning battery's going flat, a lot of people are saying that a faulty HRW relay could be draining the battery? Do the relays just pull off? I might try removing it to see if that helps.

[05omegav6]

Drive it 200 miles instead of 2, with as little turned on as you can get away with...

If that doesn't charge the battery you have bigger issues

[Entwood]

I took the car out this morning and did 4 short runs of approx 2 miles per run, over 2 hours. 3 hours later the battery was almost dead. I've been reading some posts concerning battery's going flat, a lot of people are saying that a faulty HRW relay could be draining the battery? Do the relays just pull off? I might try removing it to see if that helps.

It takes around 5-10 miles to replace what you use in one start ... so you are getting more and more into deficit ... Charge the battery up properly, 24 hours on a decent charger, if you are lucky it might survive .... 

[Ever Ready]

As others have said you really need a decent run to replenish the power used by frequent start stops, incidentally this is one of the reasons that I do not like the eco stop-start technology on modern cars

I have seen it many times over the years where people only drive say five to ten mile journeys but they have heated rear windows, headlights, blower-air con, radio etc on all the time and wonder why their battery dies after a few days