No Start: Cranks and Will Not Fire, or Does Not Crank at All

When somebody calls and says the car will not start, the first question is always the same, because the answer splits the diagnosis in half.

Does not crank

The starter is not turning the engine. You turn the key or press the button and get nothing, or a single click, or rapid clicking.

• **Rapid clicking** — usually insufficient current. Battery, terminals or a bad connection.
• **A single loud click** — the starter solenoid engaged and the motor did not turn. Starter or heavy cable connection.
• **Complete silence** — no power reaching the starter circuit. Battery, ignition switch, neutral safety or clutch switch, relay, fuse, or a security system fault.
• **Dash lights bright but nothing happens** — points away from the battery and toward the starter circuit.
• **Dash lights dim or go out when you try** — points at the battery or its connections.

Cranks but will not fire

The starter turns the engine normally and it does not start. Now the electrical system is doing its job and something in the running of the engine is missing.

• **Fuel** — pump, relay, filter, or genuinely out of fuel more often than people admit
• **Spark** — coils, plugs, crank or cam sensor
• **Compression** — timing belt or chain failure, which is the serious one
• **Security system** — an immobiliser preventing the engine running
• **A crank or cam position sensor**, which is a very common cause of a sudden no-start with no warning

Things worth checking yourself

1. 1Is there fuel in it? Gauges fail.
2. 2Does the security light behave normally, or is it flashing?
3. 3Did anything change — a jump start, a battery change, recent work?
4. 4Is it in Park, and does it start in Neutral? A failing neutral safety switch shows exactly this way.
5. 5Are the battery terminals clean and tight?

Do not keep cranking

Extended cranking overheats a starter and flattens a battery that may have been fine. If it does not start in a few attempts, stop and get it diagnosed rather than turning a small problem into two problems.