Both blowers out ??

[gapple12]

Just put the boat on my muffs for a run and I always run the blowers a few minutes before I start. Well, blowers didn’t turn on. Switch LEDs are on and I just used a test light and verified power to both blowers. What is the odds both blowers fail same time ? Both show power, but one thing I thought was strange is I’m reading power on both wires going to each blower. Should one lead be power and one be ground ?

 

[GA_Boater]

Somehow the ground for both blowers got disconnected. That's why you read voltage on both sides of the blowers - No ground.

 

[Alumarine]

I'm not sure how you are using the test light but one wire should be 12 volt and the other ground.
The light doesn't indicate that one wire is power if you are connecting it to the 2 wires.
You could connect the lead on the test light to the negative terminal of the battery or the block.

Maybe one blower went out before and you just noticed it when the other blower went.
Having said that I've never had a blower go.

 

[gapple12]

I had the negative clipped to the negative battery terminal, both wires are reading power to each blower. They were working last time out a few weeks ago

 

[gapple12]

I just don’t understand how all of a sudden the leads can show power in both sides. How can a ground fail to power ?

 

[GA_Boater]

Are you saying both wires on each blower motor are lighting the test probe with the probe grounded at the battery? So all 4 blower wires light the test probe?

You have a disconnected ground to the blowers. Trace the wire back to where ever it's connected to ground. Wiring breaks and connections fail due to corrosion.

 

[gapple12]

Yes, test light is grounded to one of the batteries and all 4 wires going to both blowers are showing power

 

[Grub54891]

Have you disconnected the blower wires completely from the blowers themselves? If not they will/could carry the power back to ground.

 

[GA_Boater]

You are seeing voltage through the motors because one side of the motors is not grounded. Like I said - Trace back. Both motors are probably grounded at the same point.

 

[gapple12]

Have you disconnected the blower wires completely from the blowers themselves? If not they will/could carry the power back to ground.

Yea, each blower has a disconnect plug, with them disconnected this is what I get, sticking the test light into the plugs

 

[Bt Doctur]

With the clip of the test light to battery ground you read 12v on both holes of the plug? the side of the plug not connected to the blowers?
If the blowers were working and now do not then was any rewiring done in the boat,
Worst case , ground both sides of the wires and see what fuse or circuit breaker pops

 

[Scott Danforth]

follow what GA has been saying in multiple posts.......you lost the ground to the blowers.... that is the only reason you would show power on both leads

 

[gapple12]

So, I tried to follow the wires and they go into a large wiring harness and go towards the drivers area. My guess is they go to the switch that I have to pull the steering wheel to access. So, I cut the grounds off both harnesses and ran them to the ground buss bar. Hit the switch and they both turned on.

 

[GA_Boater]

So, I tried to follow the wires and they go into a large wiring harness and go towards the drivers area. My guess is they go to the switch that I have to pull the steering wheel to access. So, I cut the grounds off both harnesses and ran them to the ground buss bar. Hit the switch and they both turned on.

Tole ya, tole ya and tole ya. :smile:

Test lights are nice, but suck to diagnose ground problems. A meter could check continuity to ground in 2 seconds.

Oh well - Ya got working blowers again. :thumb: