Hello, I noticed whenever I press the windscreen heater button, the voltage drops by looking at the all the lights dimming, even the driving ones at front.

Also the idle rev drops a little whenever I press the button. I am wondering if this is due to poor conductivity in the wires or if it is normal at all?

My car also just turned off at one point, only twice tho, when I engaged heated windscreen, and AC on max just after turning on the car. The battery I believe strongly is in good shape as it is indicated by the color indicator on the battery itself if its good or needs replacing. However there has been slight corrosion on terminals so there is that.

Would appreciate any advice and thanks for reading

Check the drive belt for condition. However it's not uncommon to see a slight drop in voltage when the heated front screen is turned on, as it draws a lot of amps. If it's a large voltage drop, it could be that it's had a non heated screen alternator fitted at some point, which doesn't have enough spare capacity to supply the heavy current needed to supply the front screen.

Oh and the window type battery charge indicator is a rough guide to the battery charge state, not it's condition. A better device for monitoring the vehicle electrical and changing systems is the BM2 battery monitor.

Nodge68 said:

Check the drive belt for condition. However it's not uncommon to see a slight drop in voltage when the heated front screen is turned on, as it draws a lot of amps. If it's a large voltage drop, it could be that it's had a non heated screen alternator fitted at some point, which doesn't have enough spare capacity to supply the heavy current needed to supply the front screen.

Oh and the window type battery charge indicator is a rough guide to the battery charge state, not it's condition. A better device for monitoring the vehicle electrical and changing systems is the BM2 battery monitor.

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Wow, thanks. Will definetely look into the battery monitor.

Shabe said:

Wow, thanks. Will definetely look into the battery monitor.

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Here. You need a smart phone app for it to connect to, but it stores over a months worth of data, so it's perfect for monitoring battery condition 24/7.

Nodge68 said:

Here. You need a smart phone app for it to connect to, but it stores over a months worth of data, so it's perfect for monitoring battery condition 24/7.

Bluetooth BM2 12V Battery Monitor Car Battery Analyzer Test Battery4315 | eBay

1 x Battery Monitor BM2 Bluetooth 4.0 Device Car 12V Battery Tester. Receives notifications of battery conditions in Bluetooth range. Automatic synchronization when in Bluetooth range. Works with all 12V batteries.

www.ebay.co.uk

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