Join Date: Aug 2006
Location: Greater Puget Sound Area
Re: all of a sudden clicking
The Starter relay (or solenoid) will click if the battery is low but it usually goes click,click,click... very fast clicking when the battery is low. If it just clicks once then the relay is probably the culprit. You can find out by using a volt meter (multi-meter set on the first scale higher than 12v DC). Put the positive lead on the battery side and the negative lead on the starter side. Check the voltage when you try to start it (have someone else try to start it while you watch the meter) If it reads more than 0.5 VDC then the solenoid is bad - the chances are it will read nearly battery volts in your case. If it reads battery volts then it is not completing the circuit from the battery to the starter.
(NOTE: if the battery volts are lower than 12.1 (between the + and - posts then your battery should be charged before you test the solenoid)
If the battery volts drop to less than 9VDC when cranking (or trying to crank) then the battery is either dead or it has a very reduced capacity and needs to be replaced - you can tell which one by charging the battery and retesting.
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