Question about Cobra 18 WX ST 40-Channels Base CB Radio

1 Answer

CB keeps blowing fuses

My cobra 18wx stl ll blows fuses when plugged in

Posted by on

1 Answer

  • Level 1:

    An expert who has achieved level 1.

    Corporal:

    An expert that hasĀ over 10 points.

    Problem Solver:

    An expert who has answered 5 questions.

  • Contributor
  • 14 Answers

There are a few common reasons the fuse keeps blowing:

1. The transmitter final transistor is bad, it usually is directly connected to the 12v source and not switched by the power switch.
2. The power wires were accidentally reversed I.E. positive to ground, neg to 12v. There is a protection diode on the circuit board that did its job and is now shorted. it will keep blowing fuses until its replaced.


Posted on Jan 01, 2009

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

We have a cignus 818 base radio, it blows fuse after a while, i can transmit for about a few minutes then it blows fuse.


final or main IC getting ready to burn out.Have it checked by a tech.If its the final then replace the driver also.

Mar 25, 2014 | Cobra 18 WX ST 40-Channels Base CB Radio

1 Answer

Cobra 18 wx st ll hade it for about a year, now it blows fuses when it powers up.


change the reverse polarity diode. Put one in that is one number higher like 1n4003 to a 1n4004 .It will handle more volts so you shouldn't blow any fuses.

Feb 08, 2013 | Cobra 18 WX ST 40-Channels Base CB Radio

1 Answer

Brand new Midland 5001z 40 channel cb blows fuses its turned on


Where did you buy the radio at? Can you return it to the store? If you purchased it at a big box store, like Walmart, they will take it back without a receipt on an exchange.

More than likely the radio was wired backwards by someone, which blew the protection diode, and then was returned to the store and put back on the shelf.

If it is just a blown protection diode, it is only a $10 fix at most any cb radio shop.


If I can help anymore, please let me know.

Dean Pitts
Rollin CBs
dean@rollincb.com

Feb 05, 2012 | CB Radios

1 Answer

My cobra 1000 gtl cb radio keeps blowing finals


Check bias and check your SWR. Also make sure your coax is not excessively leaky, and also check the loading coil inside the antenna to make sure the coil connections have not become all corroded and that their connections are sound.

Jan 15, 2012 | CB Radios

1 Answer

When i hook up my cobra29 LTd to my pickup it keeps blowing fuses. What do i need to do or whats wrong.


HI, my name is John. Red to hot fuse under dash or battery and black to ground hope this was helpful.... good luck John

Oct 08, 2010 | Cobra 29 LTD CB Radio

1 Answer

Cobra 75 wx st fuse keeps blowing. As soon as I plug the transceiver into the connector box the fuse blows.


Hi and welcome to FixYa,

Initially, check the reverse protection diode, D18 (1N4004). It would be located / connected at the power board of the DC connector.

Good luck and thank you for asking FixYa.

Oct 28, 2009 | Cobra 75 WX ST 40-Channels Handheld CB...

1 Answer

Blowing fuses with wiring CB to battery


Is the wire going to the battery touching chasis ground at all? Accidentally pinched it, cut wire etc? If not the the power supply may be fried.

Jun 04, 2009 | Cobra 29 LTD CB Radio

1 Answer

Blowing fuse


Your polarity protection diode has been blown. If you tried hooking up your CB and accidentally pushed the plug in backwards. Inside the radio, there are 2 big black diodes near the transformers, D8 and D23. Replace these with the same or bigger. You can the burnt one out and the radio will work, but if you hook it up wrong again, it will fry the radio.

May 02, 2009 | Cobra 29 WX NW ST 40-Channels Base CB...

1 Answer

B;owing fuses, wont power up, just smokes


Hi,

Try checking the reverse protection diode. This diode would normally be connected right after the power connector and would be the biggest diode inside. One way to verify if this is defective and causing the fuse to blow is even with the power switch at the OFF position, the fuse will still blow.

If on the other hand, the reverse protection diode is good and fuse will not blow when power switch is at OFF, then the short/defective component is inside. There would only be two (2) major components that can cause the fuse to blow with the power switch to ON, the final transistor and/or the audio IC.

Hope this be of initial help/idea. Pls post back how things turned up or should you need additional information.

Good luck and kind regards.

Thank you for using FixYa.

Jun 06, 2008 | Cobra 29 LTD CB Radio

Not finding what you are looking for?
Cobra 18 WX ST 40-Channels Base CB Radio Logo

Related Topics:

652 people viewed this question

Ask a Question

Usually answered in minutes!

Top Cobra CB Radios Experts

AnyMHz.com
AnyMHz.com

Level 2 Expert

489 Answers

Iron
Iron

Level 3 Expert

3018 Answers

Brad Brown

Level 3 Expert

13530 Answers

Are you a Cobra CB Radio Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...