Join Date: May 2014
Location: San Andreas Fault Zone
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Re: Odd Start Issue
Your battery voltage is too low to crank the starter, or to even keep the starter solenoid engaged.
The "chattering" sound from the starter is actually from the solenoid. When you turn the key to the START position, the solenoid pulls in and applies power to the starter motor. When the battery state of charge is extremely low, as soon as the solenoid closes and applies power to the starter, the battery voltage drops so low that the solenoid "drops out", and disconnects power from the starter. As soon as the load from the starter is removed, the battery voltage rises slightly, and the solenoid pulls in again. This process repeats several times a second, causing the "chattering" sound.
So, you have low battery voltage AT THE STARTER. There could be multiple causes:
a) Defective battery (low electrolyte, dead cell, high resistance in internal cell-to-cell connections, etc.)
b) High-resistance in the battery B+ connections
c) High resistance in the battery ground connections
d) Defect in the alternator output wiring
e) Opened ALT fuse
f) Failed alternator (usually worn brushes, but this will usually be seen as low voltage at idle speed, or a flickering BATT warning light)
g) High resistance in the starter wiring
h) Short circuit in the starter itself
Last edited by FJtest; 07-29-2019 at 05:59 PM.