Voltage update

Just took the car for a drive using a cable from the cigarrette lighter attached to a multimeter to read voltage.

The battery voltage when the car had been left overnight was 12.3V. I attached it to the charger which took a few mins to bring it up to 15v before it dropped to the 13.6 maintenance charge.

On starting, voltage dropped to 9v and it started easily.

At idle after starting voltage was 14.1

While driving with normal driving lights and the climate control running it was 14V, dropping to 13.9V at idle.

Adding rear-screen demister, both heated seats, full beam and air-con running flat out dropped the voltage to 13V.

We stopped the car for 15 minutes and when restarted voltage was 13.7 volts.

Over the 15 min drive home this voltage crept up to 13.9V.

Switcjing from daytime running lights (dipped beam) to sidelights made the voltage drop by around 0.05 volts.

The in-dash voltmeter consistently under-read the real voltage, more so on the drive back, possibly confirming my theory that something heat-related is affecting the system.

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