Hot ignition switch

[tmsnyder]

Anyone else experience this?   The switch on mine gets HOT to the touch.   Right around where the key is, the tumbler.


I'm thinking the switch is on its way out.  There must be some corrosion or something on the contact surfaces causing resistance, which causes voltage loss.  And voltage drop * amps equals watts of heat energy to dissipate. 


I have a new switch ordered, they are fairly inexpensive for these Chevy units. 

[Rickf1985]

Did you look at the plug? Sometimes one of the terminals on the plug will be melting.

[tmsnyder]

Indeed, the connector was looking a little melted around the IGN and BAT terminals.  The spade terminals looked fine, no corrosion, so it must be at the contacts inside the switch.  I ohmed the connection and got varying readings with a low of 7 ohm and a high of 100k.  Even 7 ohm is too high, if 10A were running through that it would be 70W being emitted by the contacts, that's a lot and would explain the hot switch. 


The switch was very inexpensive, like $30.  RockAuto has much cheaper ones but I opted for the better one.


It took me longer to figure out how to remove the key tumbler / cylinder than change the switch.  Youtube is very helpful. Just turn the key past OFF to the ACC position, stick the end of a paperclip into the hole, rotate the key a smidge more and out it pops.  Then I could unthread the collar that holds the switch in the dash panel and disconnect the wiring harness from the back of the switch.