Tip & How-To about Volkswagen Beetle

Vehicle charging and starting systems

There is confusion when a car won't start because a starter can be shorting/binding and drawing too much current or have a discontinuity and not draw enough, or a battery can have too little current or have a discontinuity preventing it from providing enough. But it is possible to tell with just a simple voltmeter or even a test light.

First you check battery terminal for being clean and greased, belts tight, enough battery water, engine not binding, etc.

Then test the battery with the engine off, and expect 12.5 volts. If less, then charge it up or replace it.

Then when you try to crank the starter, it should drop to about 10 volts.
If it does nothing and stay above 12, then it could be the ignition switch, neutral/clutch safety switch. See if the current gets to the starter solenoid. If it is getting current or it clicks, the starter solenoid is not closing the current to the starter field windings. That could be because the solenoid is bad, or the field could be burned out and open. You could try to shunt the solenoid, but it is probably easiest to just get a new starter.

If the voltage drops down to 9 or less, then either the battery does not have enough reserve, or the starter is shorting/binding and drawing too much current. The way to tell is what happens when you stop trying to crank. If the battery really is bad, it will not come back up to 12 volts, at least not right away. But if it was the starter, then it should come back to 12 when you stop drawing on it. (But don't try to crank it too long.)

Finally, lets assume you do get it started, either with a new battery, charging the old one, replacing the starter, fixing switch, etc. Then when you rev the engine, it has to put out over 13.5, so that it can charge the battery. Over 14.5 would be bad because it would overheat the battery and dry it out. But with less then 13.5, even a new battery will not last more than a couple of days. But at idle speeds expect only 12.5 or so. If you don't have a voltmeter, you can see the headlight brighten slightly when reving up.

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1997 monte carlo new battery and alternator but will only start when jumped


starter might be internally shorted or binding up causing the starter to require more amperage to turn. have a mechanic perform a starter draw test on it or take it off and have it tested. if you are going to have it tested take it to a good alternator/starter repair shop. autozone and oreillys cant simulate engine load and if its binding because of a bad bearing on the armature shaft, with out engine load it will test good

Jan 20, 2013 | 1997 Chevrolet Monte Carlo

1 Answer

i turn key and starter spin but will not engage flywheel.


You have one of two problems: Either the starter drive on your starter is defective and is not engaging the flywheel to crank the engine, or the flywheel has some broken or damaged teeth that are preventing the starter from engaging.
Starters come in a variety of designs. On some, the solenoid is mounted on top of the starter. When you turn the key, the solenoid routes current to the starter motor and at the same time pulls a lever that slides the drive gear mechanism out so it will engage the flywheel and crank the engine. If the solenoid is weak or damaged, it may not be strong enough to overcome the spring tension that retracts the drive gear. So the starter spins but doesn't crank the engine.
On other starters, the solenoid is mounted remotely. When the starter motor starts to spin, it ratchets out so the drive gear will engage the flywheel and crank the engine. If the drive mechanism is damaged or hung up, the motor may spin but not crank the engine.
Regardless of what type of starter you have, it will have to come out for further inspection. The drive gear (which is sometimes referred to as a "Bendix drive") should move out when the starter starts to spin. The drive gear usually has a one-way clutch that is supposed to protect the starter against damage if someone keeps cranking the engine once it starts. The gear should turn one way but not the other. If the gear is locked up or turns freely either way, the drive is bad and needs to be replaced. If the drive can't be replaced separately, you'll have to replace the entire starter.
Starter Testing If the drive seems okay, the starter should be "bench tested" using jumper cables or special equipment designed for this purpose.
CAUTION: Be careful because a starter develops a lot of torque. It should be held down with a strap or clamped in a vice (be careful not to crush or deform the housing!) before voltage is applied.
A simple no-load bench test can be performed with a battery and a pair of jumper cables to see if a starter motor will spin. But this test alone won't tell you if the starter is good or bad because a weak starter that lacks sufficient power to crank an engine at the proper speed (usually a minimum of 250 to 500 rpm) may still spin up to several thousand rpm when voltage is applied with no load.
A better method of determining a starter's condition is to have it tested on equipment that measures the starter's "amp draw." A good starter should normally draw a current of 60 to 150 amps, depending on the size or power rating of the starter. Some "high torque" GM starters may draw up to 250 amps, so refer to the OEM specifications to make sure the amp draw is within the acceptable range.
If the starter does not spin freely, or draws an unusually high or low number of amps, it is defective and replacement is required.
An unusually high current draw and low free turning speed typically indicate a shorted armature, grounded armature or field coils, or excessive friction within the starter itself (dirty, worn or binding bearings or bushings, a bent armature shaft or contact between the armature and field coils). The magnets in permanent magnet starters can sometimes break or separate from the housing and drag against the armature.
A starter that does not turn and draws a high current may have a ground in the terminal or field coils, or a frozen armature.
Failure to spin and zero current draw indicates an open field circuit, open armature coils, defective brushes or a defective solenoid.
Low free turning speed combined with a low current draw indicates high internal resistance (bad connections, bad brushes, open field coils or armature windings).

Jul 27, 2012 | 2005 Ford Taurus

1 Answer

how to change a starter


Starter - There are like 2 or 3 bolts on most starters that are long and go into the engine block. Then there is the electrical positive connection which should be removed only after the battery has been disconnected to avoid shock and fire caused by a short in the electrical system when disassembling or assembling (warning: this a safety measure designed to keep you from hurting yourself or the car). Assembly is the reverse of the removal.
TESTING No-Load Test Make the connections as shown in the illustration. Close the switch and compare the rpm, current and voltage readings with the specifications found in the chart located in this section. Fig. 1: Proper connections for the starter no-load test 87952035.gif
  • Current draw and no load speed within specifications indicates normal condition of the starter motor.
  • Low free speed and high current draw indicates worn bearings, a bent armature shaft, a shorted armature or grounded armature fields.
  • Failure to operate with high current draw indicates a direct ground in the terminal or fields, or frozen bearings.
  • Failure to operate with no current draw indicates an open field circuit, open armature coils, broken brush springs, worn brushes or other causes which would prevent good contact between the communtator and the brushes.
  • A low no load speed and low current draw indicates high internal resistance due to poor connections, defective leads or a dirty commutator.
  • High free speed and current draw usually indicate shorted fields or a shorted armature.
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Jul 21, 2010 | 1990 Chevrolet Cavalier

1 Answer

will not start, clicking in engine, and smoke or steam coming from engine


Sounds like something is shorting out starter.
Disconnect battery terminals,get shop manual and inspect and clean off and repair any wiring to the starter.
Reconnect and have the battery checked out (Open circuit voltage test, and load test.), do starter current draw test if a-ok put back into service. Normally I would have you do a voltage drop and current draw test on starter circuit BUT SMOKE MEANS THE SHORT WILL BE OBVIOUS. Good luck and be careful I'v eseen these things start fires and cook batteries.

Mar 14, 2010 | 1999 Ford Taurus

2 Answers

MY 2005 DODGE DURANGO WILL NOT START UNLESS IT IS JUMPED. THE BATTERY POWER WAS TESTED AT ADVANCED AUTO. ACCORDING TO THE SALES REP, THE POWER WAS GOOD (450 OUT OF 600). WHAT COULD BE THE PROBLEM?


450 out of 600 what? sounds like you have somthing drawing power need an amp meter. remove key and leave window down. disconnect negitive battery cable and connect meter between the negitive cable and negitive termainal on the battery should see around 2.5 milliamp draw or less may take 1/2 hour to get to this point. also if this vechile is not driven often this could be the problem

Aug 23, 2009 | 2005 Dodge Durango

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