Murray Diagnostic AAE MIMI

26/03/2026

2025 Ford transit custom parasitic drain.

An excuse for my thermal camera.

Complete diagnostic less than 10 minutes.💪

31/12/2025

Happy New Year🎊🎊🎊!!!

Hope to share some interesting bits in 2026👌

15/12/2025

Getting stuck into Monday. I do love ❤️ a battery job.

This is getting more common every day. This Phev Kuga the customer damaged the Coolant line that's mounted internally in the battery.

It's in Battery so level 4 IMI is required luckily SERC Motor Vehicle taught by Alan Kerr got me sorted.

Fantastic courses that opens up lots of avenues to each student!!!

19/11/2025

I think secretly we all have a soft spot for Henry's creations.

I grew up watching Stephen Finaly,Malcom Wilson,Colin McRae and my personal favourite Frank Meagher. (Oh the anti lag on a Grp A Cosworth👌)

I can still recite the registration of each of their car's. Sad I know.

Unfortunately I was hooked!!!!

I'm not saying Ford are perfect, but they'll do for me 👌👌

18/11/2025

Master Technician accreditation day!👨‍🎓📖

16/11/2025

⚡Mustang Mach E⚡ Just finished a high-voltage contactor diagnostic on a Mustang Mach-E, and honestly, this is the kind of job that reminds me why I’ve always had a soft spot for Ford. Even with all the new EV tech, you can still see that same engineering attitude shaped by years of motorsport heritage: build it tough, build it clever, and make sure the system looks after itself when something seems off.

A lot of people like to argue about the P0AA4 “High Voltage System Contactor Stuck Closed” fault. And that’s fair enough, everyone has their own experiences. But in every Mach-E I’ve worked on so far, I’ve never found a contactor actually welded or stuck shut. What I have seen is the car doing exactly what it’s meant to: spot something unusual, open the system, and keep everything safe.

And for anyone looking at the voltage reading I posted, the important bit is this: that measurement is taken on the pack side of the contactor. That’s the only place you’ll get the true pack voltage once the contactors have opened. The vehicle side bleeds down, which is your confirmation that the contactors aren’t stuck; they’ve opened like they’re supposed to.

To me, that’s the impressive part. Ford has carried the same thoughtful engineering, the sort that comes from years of motorsport and performance work, straight into their EV platform.

Some people see the P0AA4 differently, and that’s fine. All I can share is what I’ve seen firsthand: the Mach-E’s high-voltage safety strategy is solid, sensible, and genuinely good to work on.

Still happy to be swinging a spanner for the blue oval, even if the “engine” these days is more high-voltage cables than pistons.

01/11/2025

Enjoying this guy's stuff at the minute seem to do impressive work 👏

If you would like to support our content and future videos you now can here. https://buymeacoffee.com/rmsdiagnostics Welcome to the RMS Diagnostics YouTube c...

22/10/2025

Thanks to everyone for supplying some great kit.
Pico Technology (Automotive Diagnostics) Elite Diagnostic Solutions Brian Drysdale Shadow Foam Ltd. Snap-on Tools
Fluke Corporation Power Probe Europe

13/10/2025

Ford speak !!!!

Why do OEMs use different terms for components we've all been familiar with for decades?

God forbid they make our job "easy"

This one today was a 2020 Ford Ranger with the Panther engine.

DTC P007B CHARGE AIR COOLER TEMPERATURE CIRCUIT RANGE AND PERFORMANCE. The dealer wiring diagram doesn't reference this term at all.

Why not Intake air temp(IAT)? Even manifold absolute pressure/temperature (MAPT).........

Sorry, rant over.

Given the component was a pull-down device made life a bit easier to be fair.