Electronic Accessories problem on Malibu Txi MO

[John E.]

2017 Malibu Response Txi MO

All kinds of problems with my accessories:

- blower doesn't come on automatically on power up and cannot be selected but if I move the relay/fuse to the stby slot it works (continuously, unswitchable)

- heater comes on on power up and is not switchable (can't turn it off)

-bilge pump doesn't seem to be working

- Motorola Medallion MBB-400M head unit not working (is there a fuse for this)? 

 

May be due to a reverse polarity/power surge. Any troubleshooting recommendations before I take it to the shop? Switches on electronic head unit can be activated they just don't work with the accessory

Edited April 16, 2023 by John E.

[csleaver]

The first things I would check would be that there are charged batteries in good condition, clean and tight connections on the batteries, breakers, battery switch, helm ground buss, power module power cables, power distribution post, engine grounds, and starter power cable.  After that it gets a bit more involved.

[justgary]

14 hours ago, John E. said:

May be dues to a power surge.

Does this include reverse battery polarity for an instant?

[John E.]

Yes, that would be a more accurate description, I'll edit

 

Edited April 16, 2023 by John E.

[ahopkins22LSV]

Did you hook the battery up backwards? Unfortunately when I did this in our 2013txi it fried the alternator and main screen. My guess is they will test both and determine what needs to be replaced. 

[John E.]

"Did you hook the battery up backwards? Unfortunately when I did this in our 2013txi it fried the alternator and main screen. My guess is they will test both and determine what needs to be replaced."

Yes I did. After replacing a relay the boat runs fine, but the accessories are a mess. The display on the head unit appears to be fine as well, I'm thinking that the relay circuit board (Medallion 1539-10867-01 mix per mod 10OPTP) is fried. There is a red led on the upper corner of the circuit board that is slow flashing, not sure if it does that when it's powered or when there's a fault. 

The bilge pump is in fact switchable (not sure if the auto feature works) so I'm down to three issues. I can pull the relay for the heater for now, that means I'm down to two issues. The stereo probably has it's own fuse so I'll look for that (there was a fuse and it was blown so now the stereo works).

That just leaves the blower. It looks like there is an auto reset bus for the blower in the storage compartment (how do I attach a pic?), is that for the blower?

 

 

I cannot find any users manuals for these Medallion products. I found the website so I'll have to call them on Monday.

[csleaver]

The Medallion power module normally has a slow blinking red LED.  The old saying is, "If it's blinking, it's thinking".  Blinking red light is definitely a good sign.  Check all of the fuses in the power module. 

[ahopkins22LSV]

Sounds like there is more protection built into the newer boats which would be good. Hopefully you find the relays and everything starts working again!