Mercury Laser EFI test box I made up

[kls2020]

Just made up this new box after successfully trying out an earlier prototype . This plugs into the existing Mercury factory wiring between the engine harness and ECU . All 16 of the inputs/outputs connected to the ECU can be monitored at there own color coded test jack plugs with a multi-meter and DVA adapter (for the cranking tests) . Continuity tests between the factory connector back to the sensors or devices connected to the engine harness can be run . Cranking and running spark coil voltages can be checked as well as injector pair pulses/voltages without the need for the merc injector test cable .Resistances of the manifold air temp sensor and coolant temp sensor can be checked . TPS calibration can be checked and adjusted without the special merc test cable by unplugging the engine temp sensor and moving the throttle 0-100% . Using this box I can run down all of the associated ECU I/O very quickly and got all of my baseline reads on a running 200 EFI . Fuel pump voltage and current can also be monitored at jack plugs for this purpose .
The box itself is 6 x 9" so I figure I can carry it along with me in the boat and if the motor gets hard to start check out all of the ECU sensor values . I put 3 foot leads on so I can drive the boat while monitoring things . I know Mercury has a DDT tester that can do all of these tests but I just made up this thing as a cheaper troubleshooting alternative .

[silverbullet02]

Awesome! I’ve always been amazed that with the shear number of laser motors that were built there’s never been much aftermarket out there for the computers. That’s a neat setup you got.

[SilverFox579]

Nice fab work!!

[EuropeanAM]

Nice! Think I like yours better than the old one we used to have in the Dealer tools.

[kls2020]

I was contemplating adding a output to the box for pulsing injector pairs if I can fit it in ?

Thanks all for the kind responses...

[EuropeanAM]

Depends on what you're going to use to provide the "pulsing" signal...

[kls2020]

Using PWM generator with output set to freq = 25 hz and voltage = 7.65 (80% duty cycle with 9 volt battery) applied to spare pink tip injector had it pulsing pretty good .