key switch resistance ?

[benzico]

hello all, my ignition switch has continuity between the black/yellow and black cables(0.5 ohms)when turned on but when i turn the switch to crank the resistance rises to 2.3 kohms, i was expecting it to go open circuit. does anyone know the correct values ? i am asking because i have an intermitent no start/spark. my engine is a 2001 115hp efi with a merc remote control, and the kill swt is good. thanks for any input ben

 

[achris]

Re: key switch resistance ?

When the key is ON you should have an open circuit between black and black/yellow. You are measuring with the harness disconnected for the engine, yes?

Chris....

 

[benzico]

Re: key switch resistance ?

thanks for the reply, the harness is disconnected. i will have to go and check the values again but i was sure i got 0.5 ohms ON and 2.3kohms when i turn the key to crank. i am doing this check with the cables disconnected from the ign swt because i wanted to seperate the kill swt and the ign swt. cheers

 

[Howard Sterndrive]

Re: key switch resistance ?

2300 ohms is as open as an ignition switch ever needs to be.

12v and 2300 ohms is going to flow 5 millamps... that's a non issue

you can blow some electrical contact cleaner at the switch, but I wouldn't waste the time

.5 ohms on is ok too. touch the leads of your ohmmeter together and see if goes right to zero. If for example, the meter reads .3 ohms with shorted leads, your .5 ohm reading is actually representing .2 ohms across the switch....

and keep your fingers off the leads, skin conducts... 2300 ohms could be your resistance

 

[achris]

Re: key switch resistance ?

2300 ohms is as open as an ignition switch ever needs to be.

12v and 2300 ohms is going to flow 5 millamps... that's a non issue

2300ohm could be an issue. The ignition system kill wire has 400+v on it, not 12....

.5 ohms on is ok too.

No, it's not... You should have an open circuit when the key is ON. The kill wire is grounded to shut the engine OFF. That wire needs to be AWAY from ground for the engine to run. ie OPEN circuit when the KEY is ON or START.

benzico, Is this a 4 stroke engine or a 2 stroke? (values on the key are the same)

Chris.......

 

[benzico]

Re: key switch resistance ?

have checked again, key swt OFF 0.5ohms,key swt ON or CRANK 2.3kohms. so do you think that because i have a high resistance instead of an open curcuit that this could be my problem? if i disconnect the blk cable from the swt will the swt still start the engine? with the engine running i could then connect it again to shut down. cheers ben