GM 12599873 Starter Asm

For V6 models,Disconnect the cable from the negative battery terminal. Raise the front of the vehicle and support it securely on jackstands. Remove the under-engine splash shield. Disconnect the battery cable (the larger cable) and the starter control cable (the smaller cable) from the starter solenoid terminals. Remove the driveplate/torque converter access cover. Remove the starter mounting bolts and remove the starter. Installation is the reverse of removal. Be sure to tighten the starter mounting bolts. V8 models: Disconnect the cable from the negative battery terminal. Remove the air filter housing. Disconnect the battery cable (the larger cable) and the starter control cable (the smaller cable) from the starter solenoid terminals. Remove the starter mounting bolts (To detach the starter from a VS engine, remove these two bolts (use a long extension and a universal joint adapter on the socket to access these bolts)) and remove the starter. Installation is the reverse of removal. Be sure to tighten the starter mounting bolts.

It is important to not assume that the malfunctioning starting circuit is caused by the starter. First, consider several key components: Begin with clean and securely connected clamps for the battery cables. Replace all damaged battery cables with new ones. Test the battery's condition, and if it does not pass any of these tests, replace it with a new one. Check wiring and connections on the starter solenoid. Are the bolts holding the starter tight enough? Besides, confirm that the shift lever is in PARK or NEUTRAL position only? Try to check out the small wire on your test light or voltmeter for battery voltage at the solenoid while an assistant turns your ignition switch to START if nothing happens when you turn your ignition switch to START but your starter will not engage. If there are no voltages present here, make use of wiring diagrams so as to help you identify which part of your starting system circuit has failed. However, in case voltage is present while still you cannot hear any sound from your starter, then remove and bench test this kind of a component. If you suspect that your starter cranks slowly, measure cranking voltage and current from battery using an induction type ammeter while actuating engine crank mechanism. The battery voltage should never be less than 8.5 volts; besides its current draw measured by an inductive type ammeter must range between 250–400 amps during cranking operation (process). On workbenches take off and examine starters/solenoids assemblies normally if power comes into this device then it means there could be problem with its solenoid/assembly but in extreme cases a jammed engine too can lead to such situation. Is it possible to apply electricity from a battery to S-terminal then observe plunger, lever shift overrunning clutch piston drive? Now depending upon these implications we know whether our starter or solenoid has defects or whether both of them are operational together.

If the starter motor doesn't engage when turning the ignition switch to START, check for battery voltage at the solenoid by connecting a test light or voltmeter to the small wire on the starter solenoid while an assistant turns the ignition switch to START. If voltage isn't present, investigate the starting system circuit using the wiring diagrams.