Tip & How-To about Ford F-100

Rapid clicking noise when trying to start the engine?

Hi There,

You turn the key to start your engine and....
a series of rapid clicks. Your car won't start. What's going on?

That clicking noise is your starter solenoid.

Your starter needs a lot of power to turn your engine. That much power would melt your ignition switch in no time if it passed directly through it. So what happens instead is your ignition switch actuates another electric switch called a solenoid. The solenoid is a really HEAVY DUTY switch.

Inside it are two copper contacts that look like the head of a bolt only rounded. The battery is attached to one, the starter to the other. Hovering above them on a spring is a copper clad disk attached to an iron core. The iron core is inside an electro-magnet.

When you turn your key (in a perfect world), an electromagnet is activated that yanks the disk towards the contacts (Making a single decisive healthy CLICK). When they connect, the circuit is closed and the starter turns over. OK.

When things go wrong:

Low Battery:

  • The solenoid requires power to actuate.
  • The starter takes a lot more power to turn the engine.
  • When the battery is low, there isn't enough power to do both.
  • You turn the key, solenoid engages (CLICK)
  • Power goes to the starter
  • The starter tries to turn the engine
  • The draw from the starter drops the available power below the minimum needed to keep the solenoid engaged.
  • The solenoid disengages
  • The starter is no longer drawing power
  • The additional power allows the solenoid to re-engage (Click)
  • Repeat the process for as long as you have the key turned. (CLICKCLICKCLICKCLICK)
That's where those clicks are coming from and why.

The remedy:
Short term - Jump start
Long term - Charge or replace battery.


I wanted to explain what was happening rather than just saying 'dead battery, replace it'. That way you can judge for yourself whats going on.

Best regards
Mike

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1 Answer

i have a 2001 lhs and it wont start it just clicks ive had the starter tested its good what else could it be


One single click when you turn the key to start or a series of rapid clicks. If its rapid clicks the battery is dead.

Sep 05, 2013 | Cars & Trucks

1 Answer

my jeep would not start or even turn over but radio,lights all work


Any clicking noises? My first thought is lithe starter has failed. Typically if all the other accessories are working and the starter doesn't when you turn the key it's likely the starter. Usually an a single click is heard everytime you turn the key to the start position. If you heard a series of rapid clicks when you try to start you likely have a weak battery. A jump start may get you going.

Apr 11, 2013 | 2006 Jeep Commander

1 Answer

Car won't start. New battery installed recently. Only clicks when trying to start.


one single click any time you turn the key usually indicates a bad solenoid on the starter. A new starter will typical get you going.

A series of rapid clicks when you try to start usually indicates a weak battery. There could also be a bad connection at the terminals on the battery or even a poor connection at the starter.

If you get a single click and everything goes dead for a couple of seconds than you definitely have a bad connection at the battery.

Let me know what you find or if you have any questions.

Dec 28, 2011 | 2007 Chevrolet Tahoe

1 Answer

2004 ion won't start. Lights work. When I turn key don't get series of clicks, get one snap.


That symptom usually means the solenoid on the starter is bad and no longer is completing the circuit to engage the starter. A new starter will likely solve that issue. A series of rapid clicks would indicate a week battery. You can try repeatedly turning the key to the start position rapidly, sometimes the starter wil start working. You can also try tapping the starter while somebody holds the key in the start position, if the starter engages place it.

Jul 16, 2011 | Saturn Ion Cars & Trucks

2 Answers

2006 GMC Sierra when you go to start it does alot of clicking before it eventually starts


Hi DL,

Two possibilities:
  1. Weak Battery
  2. Solenoid on its last legs
Just the fact that it eventually starts points me toward the solenoid (and not the starter).

Question on the "clicking": When you turn the key, do you get one solid click or a series of rapid fire clicks?

One solid click is the solenoid. It's not transferring power to the starter. These are a LOT cheaper to replace than the starter or battery.

Rapid fire is a weak battery. You can confirm this by getting a 'Load Test' at an Auto Parts or Battery store. This simulates the load of an engine starting on your battery. It takes 5 seconds, the results are Pass or Fail.

My moneys on the solenoid

Best of luck sir

Mike

Oct 02, 2009 | 2006 GMC Sierra

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