VHF, GPS won't power up

[Great lakes pirate]

Out for my first cruise of season on Friday. Went to turn on VHF and it wouldn't fire up. Went to turn on GPS units (one garmin and one Raymarine) and same thing, no go. I checked the fuses and they are good. I also checked for power with a volt meter and it read about 11.5 to 12v to both devices.

I then hooked up an older vhf and it wouldn't fire up either.

Any idea why they wouldn't power on? I haven't used the boat since October so I may have forgot how to use it since then:huh:. Is there a "remote turn on switch" or something that needs to be on?

 

[Bt Doctur]

Exactly how did you check for power? Where did you have the meter leads?
Because if you didn't use the black ground wire going to the unit you may not have the ground connection

 

[Great lakes pirate]

I checked for power in to spots.

1) The terminal strip at the helm that supplies power to the VHF, GPS1 and GPS2 .... one lead on the main red and one on the main black. 12V

2) The plastic connector from the terminal strip that attaches to the VHF.

 

[Bt Doctur]

Did you check the continuity across the fuse holders. don't know how many time the fuse ends are corroded in the fuse holder clips and pass no current.

 

[Great lakes pirate]

I measured power after the fuse holder.

 

[Bt Doctur]

if your showing power at the main panel fuse and no power at the units ,then the internal fuses are blown(if equipped) or there is still no power in the power cords to the units. To have all 3 not operate indicates a common point for the trouble. usually the missing/broken ground connection. where do the units grounds go to?

 

[Great lakes pirate]

I will check to see if the units have an internal fuse. I am going to check into the main ground tonight to see if there is a really good connection.

Thanks for your support/info.

 

[mj_duell]

Are they all on the same ground bus? Check your ground bus for the helm if that's the case. Woops, sorry posted 3 minutes after you. Didn't see you already have that on the to do list.

--Mike

 

[Steve S]

My 340 has an "accessory" switch that runs the chartplotter...etc. When I got my 340 I thought it had a problem... simply flipping the switch fixed it.

 

[Great lakes pirate]

No luck tonight. I made sure I have 12v terminal strip again. Tightened all the ground and 12v supply to the strip. I then checked all 3 units (Garmin, Raymarine GPS and VHF) pin connectors for 12v. All 3 were good and proved that I had 12 volts all the way to the back of the units.

I then hooked up a known good VHF (again) to the "pin connector and it would not tun on.

I also pressed all of the aux switches on the dash...

 

[Bt Doctur]

If you test a known good vhf on a battery and test the power leads and show 12v and hook the vhf up and its still dead,
you are missing a good ground or a terribly corroded 12v power lead. current makes things work , not voltage.
you can have all the voltage and ground reading you want, but if the wire cannot pass the current, nothing will light up and work.,
to test either side, run jumpers from the battery. using the wiring ground for the unit , apply the +12v to the unit with the jumper , works or not
Apply the ground lead to the unit and using the units pos 12v feed see it it works,

 

[Great lakes pirate]

Problem solved. Thanks everyone for your help and trouble shooting ideas.

I used a jumper wire to run the ground wire on the terminal strip to another ground and all 3 devices started right up!

I went into the bilge and inspected the main grounding buss and noticed that one of the screws was stripped out and extreemly loose. Looked at the wire and sure enough it was wire #108, the same one that was landed on the terminal strip. Good to go!