Test ECU?

[Navarrefisher]

1. 2B013378
2. 2013/Mercury/Pro XS

Seems like my ECU isn’t getting power. I turn the key the motor will turn over but won’t start. I’m not getting any connection like I normally would via vessel view and the fuel pump doesn’t prime. What do I need to look into to first check voltage to the ECU?

[Bryanmc57]

Does it beep when you turn the key on?

[Savage]

Check the main power relay with a DVOM.

[Navarrefisher]

Which one of the 3 relays is the MPR?

I get no beep on key up also.

[Bryanmc57]

No beep on key up, check the kill switch.

[Savage]

The one with the big red wires going to it.

[EuropeanAM]

-Check Lanyard Switch (MUST be "ON")

-Check Battery and Connections (LOAD test)

-Check FUSES

-Check Main Power Relay (furthest AFT or BACK relay)

[Navarrefisher]

I bypassed the lanyard switch completely.

Tested the batteries and they’re good to go.

All fuses are good on the motor

and I switched out the MPR with one of what a think is a trim relay and it’s a no go.

Every post I can find on the motor is getting 12v. but my fuel pump and ecu won’t turn on.

Any fuses/relays I might be missing?

[Navarrefisher]

I also bridged the MPR with wire and the fuel pump turned on, so I’m assuming the ecu isn’t sending any voltage.

[Savage]

PCM does NOT "send" any voltage to the relay, it provides a ground. Lots of PCM's get fried when improper testing and jumpering occurs.

[Navarrefisher]

How to I check proper voltage to the PCM? Before I did any jumping the PCM/fuel pump wouldn’t turn on with the key on.

[EuropeanAM]

There's a purple wire hanging up near the Oil Pump. With the key ON, check for power at that purple wire (should be 12V).

Have you tried a Transom (test) keyswitch harness yet?

Aside from that, a breakout box, wiring diagram and diagnostic manual would be in order.