Kia Sorento Third Generation (2015-2020) Not Starting: Common Causes and Solutions

When a Kia Sorento from the third generation fails to start, it can be due to various issues ranging from electrical problems to fuel delivery failures. Below are detailed diagnostic steps, tools required, and repair instructions for the most common causes.

Symptoms

• Engine cranks but does not start.
• Engine does not crank at all (silent).
• Dashboard lights illuminate, but the engine does not start.
• Clicking sound when the ignition is turned.
• No dashboard lights or sounds when the key is turned.

Common Causes

1. Dead Battery
2. Faulty Starter Motor
3. Ignition Switch Issues
4. Fuel System Issues
5. Faulty Fuses or Relays
6. Engine Control Module (ECM) Issues

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Diagnostic Steps

1. Check the Battery

Symptoms: Dashboard lights dim or do not illuminate; clicking sound when turning the key.

• Tools Required: Multimeter, jumper cables, battery tester.

Steps:

1. Visual Inspection: Check for corrosion on battery terminals and loose connections.
2. Voltage Test: Use a multimeter to check battery voltage. A healthy battery should read between 12.4V - 12.7V.
3. Load Test: If voltage is low, test with a battery tester under load. Replace if weak.

2. Inspect the Starter Motor

Symptoms: Engine cranks slowly or not at all.

• Tools Required: Wrench set, multimeter, test light.

Steps:

1. Locate the Starter: Typically located near the transmission at the engine's rear.
2. Check Connections: Ensure that all electrical connections to the starter are secure.
3. Test the Starter: Use a multimeter to check for voltage at the starter when the key is turned to the "start" position.
   • If voltage is present but the starter doesn’t engage, replace the starter motor.
   • If no voltage, check the ignition switch and wiring.

3. Test the Ignition Switch

Symptoms: Dashboard lights do not illuminate; no crank.

• Tools Required: Multimeter, wiring diagram.

Steps:

1. Access the Ignition Switch: Remove the steering column cover to access the switch.
2. Check for Power: Use a multimeter to check for power at the ignition switch when the key is turned to the "on" position.
3. Replace Ignition Switch: If there’s no power, diagnose wiring issues or replace the ignition switch.

4. Assess the Fuel System

Symptoms: Cranks but does not start; fuel gauge reading low.

• Tools Required: Fuel pressure gauge, scanner tool.

Steps:

1. Check Fuel Level: Ensure there is sufficient fuel in the tank.
2. Test Fuel Pump: Use a fuel pressure gauge to check if the fuel pump is delivering the correct pressure (typically around 60-66 psi for the Sorento).
3. Scan for Codes: Use an OBD-II scanner to check for trouble codes related to the fuel system (e.g., P0087).
4. Inspect Fuel Filter and Lines: Ensure there are no clogs or leaks.

5. Check Fuses and Relays

Symptoms: No response when turning the key.

• Tools Required: Fuse puller, multimeter.

Steps:

1. Locate the Fuse Box: Check the owner's manual for the location.
2. Inspect Fuses: Pull and visually inspect fuses related to the ignition and fuel system. Replace any blown fuses.
3. Test Relays: Use a multimeter to check relays for continuity. Replace faulty relays.

6. Diagnose the Engine Control Module (ECM)

Symptoms: Cranks but does not start; multiple electronic issues.

• Tools Required: OBD-II scanner.

Steps:

1. Scan for Trouble Codes: Use an OBD-II scanner to check for ECM-related codes.
2. Check Wiring: Inspect wiring harnesses connected to the ECM for damage or corrosion.
3. Reprogram or Replace ECM: If all other systems check out, the ECM may need to be reprogrammed or replaced.

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Repair Instructions

Battery Replacement

1. Disconnect the negative terminal first, followed by the positive.
2. Remove the battery hold-down clamp.
3. Replace with a new battery, reconnect terminals (positive first).
4. Test the electrical systems.

Starter Motor Replacement

1. Disconnect the battery.
2. Remove electrical connections from the starter.
3. Unbolt the starter from the transmission.
4. Install the new starter and reconnect all connections.
5. Reconnect the battery and test.

Ignition Switch Replacement

1. Disconnect the battery.
2. Remove the steering column covers.
3. Disconnect wiring harness from the ignition switch.
4. Replace with a new ignition switch.
5. Reassemble the steering column and reconnect the battery.

Fuel Pump Replacement

1. Relieve fuel pressure from the system.
2. Disconnect battery.
3. Remove the fuel tank to access the fuel pump.
4. Replace with a new fuel pump and reassemble.
5. Reconnect battery and test fuel pressure.

Fuse/Relay Replacement

1. Identify blown fuses or faulty relays.
2. Pull out the faulty fuse or relay using a fuse puller.
3. Replace with a new fuse or relay of the same rating.
4. Test the system.

ECM Replacement

1. Disconnect battery.
2. Remove the ECM from its mounting.
3. Disconnect wiring harness.
4. Install the new ECM and reconnect all wiring.
5. Reconnect battery and perform any necessary programming.

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By following these diagnostic steps and repair instructions, you can effectively troubleshoot and resolve starting issues with a 2015-2020 Kia Sorento. Always consult the vehicle's service manual for specific torque specifications and detailed diagrams.