Welcome to our resource for MG Car Information.



MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.


What kind of meter can I install that will give me a constant reading of the battery condition, whether the car is running or off?

SPW Wincze


I use a CTEK MXS 5 battery charger for the TF. Very pleased with this
device. Can also be used for Motor bikes etc. (No financial interest).

Rob Grantham
Rob Grantham

Thanks Rob, but the ctek will not give me the visual result that I am after. I want to be able to see the condition of the battery on a meter as I am walking by it, without having it plugged in to a wall outlet.

SPW Wincze

Try this one

Might have to " cut and paste "
M Grogan

Connects direct to battery full time

M Grogan

With the voltmeter on all the time, would that drain the battery over time?
Most of the voltmeters I've seen are wired into the ignition so only light up when the vehicle is running.

I guess you could wire in an impulse switch.

My latest battery has a permanent condition monitor - the 'Green Light' visible through a lens in the top of the battery. It is actually a built in hydrometer in one cell, so won't tell you if other cells have problems.

My TF lives in the garage with the right side of the bonnet open, so I can just check battery state while walking by. In fact, after the car hadn't run for several weeks, I noticed the lack of green light last night and put the charger on.

Steve, if you aren't fanatical about total originality, this should meet your needs.

D A Provan

Google "SparkBright"
Very simple, uses little power, works a
C Martin

That Sparkbrite is very nice Colin. What a shame that I'm colourblind.
Willem van der Veer

I think that Steve is more interested in a digital voltage display, as shown by Mike, rather than a go/nogo of the SparkBright unit. There are some available that will mount on the bottom of the fascia and are only about an inch by half an inch. My A/F ratio display is that type. I'll see what I can Google up. Bud
Bud Krueger


Displays battery voltage and % charge. ~$20 Bud
Bud Krueger

Thanks Bud,, just what I am looking for,,Thank You! could even wire in a switch so it doesnt draw all the time..

SPW Wincze


It comes with an on/off switch.

James Neel

Unfortunately, none of your suggestions monitor or measure the most critical value; and that is cranking power or CURRENT (amps). In all your cases, you are monitoring only voltage, and an almost dead battery with no load on it, can usually read the rated voltage. (ie:13.8 volts)

What you REALLY want, is the ability of the battery to perform at its rated specifications, and measuring voltage is the weaker of the two choices (the other being current, or amps).

Current potential can only be measured by shunting a dead short across the battery and measuring the voltage (drop) passing through the shunt.

As an automatic function, this not easily, or technically or inexpensively, done. There are lots of inexpensive current testers available that will do the job, but the test must be manually performed.

Expect to pay between $40 and $100 for the right tool. Google "battery load tester" for choices.

Sorry Steve, but battery "condition" should include its ability to crank the engine (starter) and I don't know of an affordable, automatic device.

Gord Clark
Rockburn, Qué.
Gord Clark

This thread was discussed between 20/07/2017 and 21/07/2017

MG TD TF 1500 index

This thread is from the archive. The Live MG TD TF 1500 BBS is active now.