Question 1

What does Suzuki fault code Code 12 mean?

Accepted Answer

Code 12 (Diagnostics / Baseline): CEL Flashes 1-2 Pattern / Normal Run Fix: LOGIC: Normal Diagnostic System Output (No Fault Stored).

ACTION: Jumper diagnostic diagnosis terminal to ground in 6-pin/16-pin DLC under dash. Count flashes (one flash, pause, two flashes = 12). If drivability issues persist without codes, check mechanical fuel pressure and valve lash clearance.

Question 2

What does Suzuki fault code Code 13 / P0130 mean?

Accepted Answer

Code 13 / P0130 (Fuel / Oxygen): High Fuel Consumption / Black Tailpipe Soot Fix: LOGIC: Heated Oxygen Sensor 1 Circuit Inactive or Shorted.

ACTION: Disconnect single-wire or 4-wire O2 sensor pigtail at exhaust downpipe under seat. Measure heater resistance across white wires (spec: ~5–7Ω); check signal output while hot (should swing rapidly 0.1V to 0.9V).

Question 3

What does Suzuki fault code Code 14 / P0115 mean?

Accepted Answer

Code 14 / P0115 (Cooling / Thermal): Floods on Hot Restart / Fast Idle Sticks Fix: LOGIC: Engine Coolant Temperature (ECT) Sensor Signal High / Open.

ACTION: Access thermostat housing under bed access hatch. Disconnect 2-pin ECT sensor. Test thermistor resistance (spec: ~2.0k–3.0kΩ at 20°C, drops to ~300Ω hot); verify 5V reference wire from ECU.

Question 4

What does Suzuki fault code Code 15 / P0117 mean?

Accepted Answer

Code 15 / P0117 (Cooling / Thermal): Radiator Fan Runs Continuously / Hard Start Fix: LOGIC: Engine Coolant Temperature Sensor Signal Short to Ground.

ACTION: Measure ECT signal pin resistance to chassis ground (must be infinite with sensor unplugged). Inspect sub-harness where it passes over the aluminum intake manifold runner for melted loom.

Question 5

What does Suzuki fault code Code 21 / P0120 mean?

Accepted Answer

Code 21 / P0120 (Throttle / Controls): Hesitation Off-Idle / Bucking on Accel Fix: LOGIC: Throttle Position Sensor (TPS) Circuit Voltage Out of Range.

ACTION: Check 3-pin or 4-pin TPS connector on throttle body. Backprobe signal wire (yellow/blue) to ground; verify smooth sweep without voltage dropouts (spec: ~0.5V closed to ~4.2V wide open).

Question 6

What does Suzuki fault code Code 24 / P0500 mean?

Accepted Answer

Code 24 / P0500 (Speed Sensing): Speedometer Inop / Engine Surges at Coast Fix: LOGIC: Vehicle Speed Sensor (VSS) Reed Switch Signal Missing.

ACTION: Remove instrument cluster or transmission tailhousing speed pickup. On cable-driven models, test the magnetic reed switch behind speedometer head; on electronic models, check 3-pin Hall-effect sensor.

Question 7

What does Suzuki fault code Code 31 / P0105 mean?

Accepted Answer

Code 31 / P0105 (Air Induction): Rough Low Idle / Stalling When Shifting Fix: LOGIC: Manifold Absolute Pressure (MAP) Sensor Circuit Error.

ACTION: Inspect small rubber vacuum line running between intake plenum and firewall-mounted MAP sensor. Clear oil sludge from sensor vacuum port; verify 5V reference and ~1.2–1.8V output at warm idle.

Question 8

What does Suzuki fault code Code 34 / P0340 mean?

Accepted Answer

Code 34 / P0340 (Timing / Cam): Extended Cranking / Crank No-Start Cold Fix: LOGIC: Camshaft Position Sensor Signal Loss.

ACTION: Disconnect CMP sensor on top rear of cylinder head. Check 3-pin plug for engine oil wicking through sensor body. Measure sensor power, ground, and square-wave digital output during cranking.

Question 9

What does Suzuki fault code Code 42 / P0335 mean?

Accepted Answer

Code 42 / P0335 (Timing / Crank): Crank No-Start / Tachometer Needle Dead Fix: LOGIC: Crankshaft Position (CKP) Sensor Circuit Malfunction.

ACTION: Locate CKP sensor by the lower bellhousing / flywheel. Measure inductive coil resistance (spec: ~900–1,300Ω) or inspect Hall-effect 12V supply; clean clutch dust fuzz off sensor magnetic face.

Question 10

What does Suzuki fault code P0171 mean?

Accepted Answer

P0171 (Fuel / Metering): Lean Hesitation / White Spark Plug Porcelain Fix: LOGIC: Fuel Trim System Too Lean (Bank 1).

ACTION: Check for cracked intake air plenum boots downstream of air filter under bed. Measure fuel pressure at delivery line (spec: ~2.8–3.2 bar); clean varnished 12-hole micro fuel injector tips.

Code	System	Symptom	Full fix
Code 12	Diagnostics / Baseline	CEL Flashes 1-2 Pattern / Normal Run	View fix
Code 13 / P0130	Fuel / Oxygen	High Fuel Consumption / Black Tailpipe Soot	View fix
Code 14 / P0115	Cooling / Thermal	Floods on Hot Restart / Fast Idle Sticks	View fix
Code 15 / P0117	Cooling / Thermal	Radiator Fan Runs Continuously / Hard Start	View fix
Code 21 / P0120	Throttle / Controls	Hesitation Off-Idle / Bucking on Accel	View fix
Code 24 / P0500	Speed Sensing	Speedometer Inop / Engine Surges at Coast	View fix
Code 31 / P0105	Air Induction	Rough Low Idle / Stalling When Shifting	View fix
Code 34 / P0340	Timing / Cam	Extended Cranking / Crank No-Start Cold	View fix
Code 42 / P0335	Timing / Crank	Crank No-Start / Tachometer Needle Dead	View fix
P0171	Fuel / Metering	Lean Hesitation / White Spark Plug Porcelain	View fix
P0219	Engine	MIL Flashing	View fix
P0300	Ignition / Misfire	Engine Shudders Under Load / Flashing CEL	View fix
P0301	Ignition / Misfire	Dead Cylinder 1 / Exhaust Stumble	View fix
P0335	Engine	Hard Start	View fix
P0400	EGR System	Knock on Acceleration / Flat Mid-Range	View fix
P0420	Emissions / Exhaust	Check Engine Light Solid / Tailpipe Odor	View fix
P0505	Air / Idle	Engine Dies at Red Lights / Surges 1500 RPM	View fix
P0562	Electrical System	Cluster Dims / EPS Heavy / Random Stall	View fix
P0605	Engine Control	Engine Won't Rev Past 2000 RPM / CEL Solid	View fix
P1614	Safety / Immobilizer	Engine Cranks But Refuses to Fire / Key Light	View fix
P1870	4WD / Drivetrain	4WD Indicator Flashes / Front Wheels Won't Drive	View fix
P1875	4WD / Axle	Axle Lock Stays Engaged / Light Won't Extinguish	View fix

Suzuki Fault Codes

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