Cigarette lighter fuse....

[rbharvey]

Before I go on a back breaking excursion, does anybody know where the fuse is for the lighter plug is off hand?

 

Looks like it ignores the CB panel and goes through the firewall to the engine/cowl area. This for late mode long bodies

 

Bob

[scottfromiowa]

Not on my '66 E.  I know because I tripped the breaker when I used a Dremel...

[Immelman]

Persons prior to my ownership installed several fuse holders (not pilot accessible) behind the circuit breakers in the lower-right portion of the instrument panel in my 66E.

As an aside, if I ever re-do that side of the panel I'd like to just get a panel cut with a hole for one CB for each item and lose all the fuse holders.

[rbharvey]

this is the factory installed plug, and there is no CB for it

 

Bob

[carusoam]

Bob,

I don't have the POH wiring diagram handy, but it should indicate that there is (or isn't) a fuse on the line.

I have not hunted it down in my M20R.  Best I can tell, what makes sense in my M20C may still makes sense for the R/M/S/T.

There is no real need for the single wire plug to extend any further than the nearest source of electricity.  The wire was only a few inches long behind the panel with a standard fuse in between it and the electrical bus.  The ground is supplied by the socket attached to the instrument panel.  (keep this in mind for those hooking up dremels, your radios may be sharing the same ground???).  Therefore, I would not expect you to have to hunt on the hot side of the firewall for this one. 

I would be thinking that if you reach under the panel you won't need to go too far.  The cigarette lighter is in approximately the same place on both short and long bodies, the electrical bus isn't much further away either, and the same glass fuse with a wire in it is probably the norm.

The only thing you might find differently, is this wire is probably tidied up with other wires under the instrument panel.  The fuse holders are often lost in a bundle held together with tie wraps.

Long body story - shortened.... follow the single lead out of the back of the cigarette lighter, it will probably lead you directly to an inline fuse.  I would not expect it to go any further than the nearest spot on the bus.

Whish I had my documents on line....

Best regards,

-a-

 

 

 

[scottfromiowa]

Caruso...understood.  That goes for those powering their 52" widescreens and hot tubs too!

[Piloto]

Your M20TN is 28V and the lighter jack is 14V. There is a down converter to lower the voltage. The CB may not be labeled Cigar Lighter but something else. Connect a device to the lighter jack and pull the suspected CBs one at a time. In some models the Lighter shares the CB of other systems.

José 

[laytonl]

Does your overhead light work?  In my M20J, there is a fuse in the avionics bay for the overhead light and the cigerette lighter.

Lee

 

[rbharvey]

Thanks for the replies, guess I will cycle all CBs and see if it comes back, but I dont think that is where the problem lies, cause im sure something else wouldnt be working too which isnt the case. Ill chase the single wire after that ...

 

Bob

[rbharvey]

In case anyone is interested, there is a step down power supply on the  rear bulkhead in the avionics bay with a fuse.....not sure what else it powers besides the cigarette lighter but it cant be much. I couldnt find anything else that didnt work when it was blown.

[M20TN_Driver]

Hi Folks--Old thread here.  Not sure if anyone came up with a solution or could point out a place for me to hunt down a fuse?  

I have a 2008 Acclaim and both Cigarette sockets went INOP within the last month or so.  No clue why and no idea where to even start looking for a fuse or whatever may run both adapters.  In my plane, there is one in the panel, and one in the rear passnger arm rest--a multi-meter confirms both are INOP.  All help appreicated.

Mike Macey

N242WT

[PT20J]

Are any breakers popped? In my J, the cigar lighter was powered by the starter breaker (no fuse). 

[M20TN_Driver]

I don't see any that are popped.  I cycled pretty much all of them.  I found the downconverter from the 24v to 12V in the rear bulkhead in the avionics bay.  There are also two breakers back there for "forward and aft 14V". I cycled those too with no affect.  

I'm not sure where the downconveter is getting its power from.  Its a mass of wires back there in the Acclaim.

[M20TN_Driver]

I don't see any that are popped.  I cycled pretty much all of them.  I found the downconverter from the 24v to 12V in the rear bulkhead in the avionics bay.  There are also two breakers back there for "forward and aft 14V". I cycled those too with no affect.  

I'm not sure where the downconveter is getting its power from.  Its a mass of wires back there in the Acclaim.

I will also note that there is an inline fuse coming to the "input" side of the converter.  Picture attached.

[M20TN_Driver]

It should have read "24v to 14v" above.   The inline fuse I checked and it is not the problem.

What would be really helpful is to figure out where this bad boy gets its power source from. 

Edited March 21, 2022 by M20TN_Driver

[Aerodon]

That was well installed, fuse on the input side (or is that a connector?), then circuit breaker on both the oullets.  The fuse on the input side should be really near the battery or the busbar that supplies it - should not be too difficult to trace?

Get your voltmeter out, maybe the converter has failed?

 

Aerodon

 

 

 

[carusoam]

TN_D!

You have the best prepared question ever!

The most modern Long bodies have that CB panel in the tail…

Older Long Bodies sent 24Vs to the sockets…

There are wiring diagrams available… available through your favorite MSC…

But, with as much info as you have there… checking with a volt meter will probably find your answer faster than looking it up in a drawing…

See if anything fell into the socket to trip a fuse or CB…

Then find that power is getting to the fuse in your hand…

There may be a big fuse or CB to supply the equipment buss back there… similar to the avionics bus protection…

See if @M20Doc is familiar with a master CB or fuse to supply the long bodies radio shelf’s CB Buss…

 

Sooo close….

PP Thoughts only, not a mechanic…

Best regards,

-a-

[PaulM]

The Wiring diagram for a 2005 M20M shows a fuse between the battery #2 relay and the voltage converter. 

Rather than say all of the fuses look fine, what are the voltages on the orange wire (28v) and red wire (14v) 

[M20TN_Driver]

Thanks for the guidance.  Right now I have been traveling and have not fully investigated.  When i put the multi-meter on the supply side where the fuse connects to the battery supply wire, I am getting 0.  Which was telling me the converter was likely not even getting charge, so looking for the feed to it and as PaulM mentioned--was hoping there is another fuse back there.  The one in the picture tested fine.

[A64Pilot]

Being that it’s fused, and back there at the battery, I’m going to guess a direct connection just like clock keep alive power, if the cigarette lighter receptacles keep power with the master off, that sort of supports my theory.

‘If so look for the same gauge wire to be directly connected to the + side of the battery, or maybe the battery relay

Just a SWAG though

Edited March 24, 2022 by A64Pilot

[LANCECASPER]

The lighter sockets on the M20TN do not keep power with the Master off.

[A64Pilot]

22 minutes ago, LANCECASPER said:

The lighter sockets on the M20TN do not keep power with the Master off.

Could still get power from the switched side of the master relay though, just guessing, but it’s not logical to me for it to get power from all the way up at the instrument panel.

Anyone have the wiring diagram?

[carusoam]

The battery relay next to the #1 battery… has a few wires connected to it…

May be a place to find interesting things connected to the hot side of the relay…. 
 

#1 is on the pilot’s side…. Close to where the access panel is…

Expect the problem to be as far away and hidden as possible…. This relay is in a too friendly location… 

-a-

[M20TN_Driver]

Thanks for all of the help on this folks--finally got to the bottom of this.  Dead downconverter was the culprit.  No idea why my multi-meter showed it getting no power....I can only assume I did not make contact at the bottom of the fuse holder. 

It is a strange setup as the cigarette adapter in the M20-TN are breakered in the avionics bay behind the rear bulkhead.  it is powered from the right side battery and has a single inline fuse only.  SO, for the gentleman that started the thread, I can only say this is where all the good stuff is found on the Acclaim.  Good news is that I was able to source a replacement unit for $20 off ebay!  They want $500 for them new.

[carusoam]

Great follow-up TN_D!

Best regards,

-a-