Over 90% of two-wheeler diagnostic scans in India boil down to the same 10 DTC codes: P0122 (TPS), P0130 (O2), P0117 (EOT), P0107 (MAP), P0335 (CKP), P0201 (Injector), P0351 (Ignition Coil), P0505 (IACV), and P1505 (Roll-Over). Here is how to diagnose each one with a multimeter.
1 P0122 / P0123 — Throttle Position Sensor (TPS)
Symptoms: Jerking on sudden acceleration, poor throttle response, abnormal idle RPM.
Multimeter Test:
• Pin 1 (5V VRef): Must measure 4.85V–5.15V DC from ECU.
• Pin 2 (Signal): 0.45V–0.65V DC at closed throttle; smooth sweep to 4.0V–4.3V DC at full throttle.
• Pin 3 (Ground): Resistance to battery ground < 0.2Ω.
2 P0130 / P0134 / P0135 — Oxygen (O2) Sensor
Symptoms: Severe drop in mileage, black sooty spark plug, rich exhaust smell.
Multimeter Test:
• Heater Winding (White-to-White wires): 6.0Ω to 16.0Ω resistance.
• Signal Wire: In warm idle (80°C+), voltage must oscillate dynamically between 0.1V and 0.9V DC.
3 P0117 / P0118 — Engine Oil / Coolant Temp (EOT/ECT)
Symptoms: Cold starting missing, high racing idle RPM, excessive black smoke.
Multimeter Test:
• Cold Engine (25°C): 2.5kΩ – 3.2kΩ (2500–3200 Ohms).
• Hot Engine (80°C): 200Ω – 350Ω.
4 P0107 / P0108 — Manifold Absolute Pressure (MAP)
Symptoms: Engine bogging under load, poor hill climbing power, throttle lag.
Multimeter Test:
• Key ON Engine OFF (Atmospheric): 3.8V – 4.2V DC.
• Idle Engine (Manifold Vacuum): 1.1V – 1.6V DC.
5 P0335 / P0336 — Crankshaft Position (CKP) Pickup
Symptoms: Engine cranks continuously but zero spark from plug cap, intermittent cutting out.
Multimeter Test:
• Resistance: 180Ω to 260Ω across pickup coil terminals.
• AC Signal: 1.0V to 3.5V AC generated while cranking self-start.
6 P0201 — Fuel Injector Circuit
Symptoms: Complete engine misfire, dry spark plug, no fuel delivery.
Multimeter Test:
• Coil Resistance: 11.5Ω to 14.5Ω at 20°C.
• Power Supply: Full battery 12V DC on Pin 1 with ignition ON.
7 P0351 — Ignition Coil Primary Circuit
Symptoms: Sudden engine stalling when riding, no high-tension spark.
Multimeter Test:
• Primary Winding: 0.8Ω to 1.8Ω.
• Secondary Winding: 8.5kΩ to 15.0kΩ (including plug cap).
8 P0505 — Idle Air Control (IACV) / Stepper
Symptoms: Bike turns off at traffic signals, RPM hunts up and down between 1,200 and 2,500.
Multimeter Test:
• 4-Pin Stepper Coils: Phase A (Pins 1–2) and Phase B (Pins 3–4) must each measure 30Ω to 45Ω.
9 P1505 / P1508 — Bank Angle / Side Stand Interlock
Symptoms: Starter motor cranks freely but zero fuel pump priming and zero spark.
Multimeter Test:
• Bank Angle Sensor: 0.6V to 1.2V DC upright. If tilted >60°, jumps to 3.8V–4.4V DC.
• Side Stand Switch: Continuity (0Ω) when stand is UP; Open circuit (OL) when stand is DOWN.