Help with Troubleshooting Bilge Pump

My friend has a 2002 Ski Nautique SE. with Chevy engine. It does not have a keypad like a Ltd or push breakers like some older models.

Nor does his boat have the PME Bypass that my 2002 SN Ltd edition has. My PME Bypass has a toggle switch with a Bilge Pump Circuit Breaker. Mine is GT 40, his is Chevy,

His inoperative bilge pump has 2 wires Brown & Black. He pulled the connector apart and tested the wires leading towards the dash with a VOM .. No volt reading with key on and bilge switch On or Off. Check of the starting battery showed 12.4 V and confirmed VOM was working properly.

Next he pulled and inspected the blade fuses under the dash near where the captain's right knee would be. All fuses appear to be intact. Is there a separate breaker fuse we are missing?

There are 3 rocker switches in a row and daisy chained together. From Port side to Starboard there is Nav Lights, Bilge Pump and then Horn. The bottom backside of the individual switches have 2 brown wires which I believe are ground. The tops of the switches are daisy chained with 2 blue wires that I believe to be power to light up the switches and also 2 black wires that power the bilge etc. This is as I recall from looking over the shoulder but I can double check.

He moved horn wires over to the back of the bilge switch. Press the Bilge switch and the horn sounded. So bilge switch seems OK?

What is the proper procedure for testing the wires for 12V? Key on with switch on, then pull a black and brown wire off back of switch and test with VOM leads? Pull one Black wire and test with alternate brown wires at the bottom? Then pull other Black wire and test with alternate Brown wires? No VOM reading but maybe he did not get the proper combination of wires.

Any suggestions appreciated. Seems simple but it's not working out to be the 30 minute job we thought.