Basic, Better, Best – Multimeters

We used to think car electrics were a dark art and the only way to have a fighting chance of diagnosing a pesky wiring issue would be to perform some kind of archaic ritual whereby prayers are recited to an imaginary higher being whilst perhaps offering a sacrificial farm animal. It needn’t be this way though. Yes, electrical problems can be some of the most difficult issues to pinpoint when it comes to classic car maintenance but that’s only the case if you don’t have the correct tools for the job, one of which being a decent multimeter.

It’s a must have bit of kit for any classic car whisperer as far as we’re concerned and without one you’re just fumbling around in the dark, with one hand tied behind your back, standing on one leg. Usually hand-held, multimeters come in various shapes and sizes but their basic functionality remains the same across the board with two leads that measure voltage, current and resistance between two points. They can be used to test batteries and circuits, find “leaks” and diagnose myriad issues with your car’s electrical system. We wouldn’t be without one and neither should you.

Not only that but they can be used around the house too so they’re not just limited to the garage. Bonus. There are a few things to bear in mind when choosing a multimeter though, such as accuracy, functionality and how physically robust it is and so with that in mind we have picked three units that run the basic, better, best gamut.

Basic

Avoiding anything too cheap and cheerful as they can be flaky at best our basic pick is this AstroAI digital multimeter which still has a lot of useful features and is clear and easy to operate. With a backlit display as well as a handy torch, visual and audio alerts and a memory function that can remember measured values, it has some great functionality. The unit is safe and accurate and also features non-contact voltage detection whereby it merely has to be placed close to electrical sockets, outlets or terminals to test voltage and live wires safely. Powered by two AAA batteries it has a low-power indicator as well as auto shut-off.

Better

For those with a little more cash to burn then the Klein Tools MM400 is a solid choice. Not only does it measure voltage, current and resistance but it can also measure temperature, capacitance, frequency, duty-cycle, and test diodes and continuity. It’s a hardy thing too and can apparently withstand a 1 metre drop – prefect for us clumsy lot. The built-in stand is more useful than you would think as well and it comes with test leads, thermocouple with adapter and batteries, so everything you need to start digging into your classic’s non-starting issue.

Best

Fluke are a bit of a heavy hitter in the industry and it’s easy to see why with their 114 model multimeter. It isn’t cheap at £150 but it will probably be the last multimeter you’ll ever have to buy. Renowned for their quality, Fluke have a well deserved reputation for producing accurate, long-lasting electrical meters and the 114 is no exception. It comes with all of the functionality you would need in a compact package but that’s not to say it’s difficult to read as the display is large, clear and backlit. The 114 also has a low impedance function (Auto-V/LoZ) which automatically determines whether the measured signal is AC or DC voltage, selects the correct function and range, and displays the correct information. It also presents a low impedance input to the circuit under test which reduces the possibility of false readings due to ghost voltages from nearby wires and circuits and improves accuracy. Fancy stuff but incredibly useful.

With a properly functioning electrical system being at the heart of an efficient, reliable classic car you simply cannot be without a good multimeter in your toolbox. Pick one of these listed here and make electrical gremlins a thing of the past. Even if you’re unable to fix the issue at least you’ll know what’s causing it and all without an incantation or a chicken in sight.