voltage on blk/yel (kill wire)

dargel167

Cadet
Joined
Feb 28, 2009
Messages
7
I have a 89 100 hp mariner 4 cyl. serial # oc135659.I have 4-5 volts on the blk/yel kill wire.I think it has ruined my switchbox.I tested it with my multi-meter (wire off switchbox terminal)to ground.the problem is in the wiring harness or the ign. switch.Does anyone know of way to find the problem.any help would be appreciated.THANKS...........dargel167
 
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Texasmark

Supreme Mariner
Joined
Dec 20, 2005
Messages
14,687
Re: voltage on blk/yel (kill wire)

At www.ebasicpower.com you can download a PDF that covers CDI troubleshooting and I KNOW you will find it an invaluable asset. Saves me a lot of typing and gets rid of any mistakes in judgement I may make. It covers the major brands and identifies wiring color code and other goodies you will need. I just briefly scanned it and have added it as a Bookmarked page in my computer.

If you come upon the term DVA and it is talking about a piece of test equipment, it is apparently a regular DVM but it has a separate scale (DVA) for use with a Direct Voltage Adapter that must come with that instrument. The Merc Part Number for the instrument is 91-99750.

I can only assume that this is a high voltage probe that allows you to use your DVM in measuring voltages that are above the normal range of your normal multimeter and since it skews the actual voltage the meter sees, it need a separate scale calibrated to it's resistance ratio.

I don't know the resistance ratio, so I can't tell you what the voltage really is and since they are making CDI voltage measurements, you will have to understand what it is measuring if you don't have one and try to use your regular DVM.

You might shoot a question to Silvertip, or Chris1956, or Bob VT, or Tashasdaddy or anyone else in the know and see how you make measurements with the normal VOM (DVM).

Mark
 

Faztbullet

Supreme Mariner
Joined
Mar 2, 2008
Messages
15,920
Re: voltage on blk/yel (kill wire)

90% of the time its a defective key switch. A easy way to check is to remove keyswitch and disconnect "kill wire", then check to see if you have voltage at pack,if not wiring ok and replace switch.
 

Barnacle_Bill

Admiral
Joined
Feb 8, 2004
Messages
6,469
Re: voltage on blk/yel (kill wire)

It is normal to have voltage on the black/yellow wire when the key is in the run postion. However in the off position there should be no voltage as that wire is suppose to be grounded.
 

CharlieB

Vice Admiral
Joined
Apr 10, 2007
Messages
5,617
Re: voltage on blk/yel (kill wire)

If I may clarify that posters statement 'voltage on the Yellow/black kill wire'


With the motor OFF, and the ignition switch turned ON, there should be NO VOLTAGE on the Yellow w/black wire.

If the motor is cranking OR running, then voltage may be present from the ignition module, grounding this kills the ignition to kill the motor.

It can be easy to test with a common Volt/Ohms Meter.

DISCONNECT the Yellow w/black wire from the ignition module on the motor, then test Ohms to Ground with the ignition switch OFF, you should have GOOD continuity.

Switch your meter to volts, turn the ignition switch ON and test for Voltage, you should have NONE, if ANY VOLTAGE, disconnect the yellow w/black wire from the ignition switch and retest, If now you have NO VOLTAGE then replace the ignition switch.

Battery voltage supplied to the Yellow w/ black kill wire WILL DESTROY an ignition module.
 

dargel167

Cadet
Joined
Feb 28, 2009
Messages
7
Re: voltage on blk/yel (kill wire)

Thanks for all the input from you guys.I suspected the ignition key switch so I blew it out with compressed air, then alcohol ,then corrosion X.It dropped the voltage down to not more than .65,so I figured it was the key switch.I replaced it & now the voltage does not go over .135 v,which I guess is normal.THANKS for everybodys help.I appreciate it......dargel 167
 
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