FAQ
TL;DR: Grand Vitara 2.0 J20A cam sensor uses 3 pins (1:+12V, 2→ECU pin 54, 3: ground); “Error: p0340 A camshaft sensor signal” can appear only after engine start; flooding and connectors matter. [Elektroda, Raywood, post #17007148]
Why it matters: This FAQ helps DIYers quickly trace P0340 and pinout faults on Suzuki J20A without chasing the wrong wire.
Quick Facts
- Pinout reported: 1 = +12 V, 2 = signal to ECU pin 54, 3 = ground; tach may drop when faulted. [Elektroda, Raywood, post #17007148]
- J20A diagram note: cam signal should be on ECU pin 52 per schematic guidance. [Elektroda, Pawel wawa, post #17006376]
- Supply noted as 12 V on sensor despite a 5 V description in docs; validate with a meter. [Elektroda, Pawel wawa, post #17006988]
- Verified root cause case: 1-tooth cam timing offset produced the P0340 symptom. [Elektroda, Raywood, post #17169522]
- Wiring diagram shared for 2000–2006 Grand Vitara J20 models (schematic excerpt). [Elektroda, pteter, post #17146025]
What is the camshaft position sensor pinout on the Suzuki Grand Vitara J20A?
Reported by the OP after testing: Pin 1 = +12 V, Pin 2 = signal to ECU pin 54, Pin 3 = ground. This configuration produced a non‑moving tach during the fault and a P0340 code after starting, but the engine ran normally after clearing. [Elektroda, Raywood, post #17007148]
According to the J20A diagram, which ECU pin carries the cam signal?
The camshaft sensor signal is specified to go to ECU pin 52 per the J20A schematic note. The author also identifies sensor pin order as 1 = +5 V (supply description), 3 = ground, and middle as signal. "Extreme pins ... 1. power supply, 3. ground" clarifies orientation. [Elektroda, Pawel wawa, post #17006376]
Should I see 5 V or 12 V at the cam sensor on J20A?
Expect 12 V present at the cam sensor feed as derived from the diagram, even though some descriptions list 5 V. The expert warns that documentation errors occur, and stresses verifying the signal line to the ECU with an oscilloscope or a diode. [Elektroda, Pawel wawa, post #17006988]
Why do I get P0340 only right after starting, then it clears?
This exact behavior was observed: the code P0340 appears after the first start, the tachometer drops, and clearing the code restores normal running. In that case, the sensor was replaced, wiring was checked, and attention shifted to timing and flood‑related connectors. [Elektroda, Raywood, post #17007148]
Can a one‑tooth cam timing error trigger P0340 on the J20A?
Yes. The thread author later confirmed the fault was mechanical: the cam timing was off by one tooth. After correcting the timing, the P0340 symptom resolved. "1 clove on the camshaft" translates to one tooth misalignment. [Elektroda, Raywood, post #17169522]
How can I quickly check if the cam signal reaches the ECU without full tooling?
Use an oscilloscope for a clean view or a simple diode test to confirm the signal toggles at the ECU pin. The advisor emphasizes that the signal wire integrity matters more than nominal supply voltage numbers when diagnosing. [Elektroda, Pawel wawa, post #17006988]
Could the starter or crankshaft speed sensor be causing my no‑tach symptom?
Yes. The expert points to possible starter issues and suggests checking the crankshaft speed sensor. He adds that the cam (roller) sensor does not drive the tachometer, so a dead tach does not prove the cam sensor failed. [Elektroda, Pawel wawa, post #17007166]
If the crankshaft sensor fails on J20A, will the engine ever start?
No. A damaged crankshaft (shaft) sensor prevents starting entirely. Quote: "If the shaft sensor is damaged, it would never fire." This helps separate crank vs. cam sensor diagnosis when facing intermittent P0340. [Elektroda, citromaniak, post #17145416]
Where is the crankshaft sensor located on the J20A, and how hard is it to access?
It sits hidden near the flywheel; accessing it can require removing the gearbox and flywheel. The connector plug is above the transmission, which you can reach to test the harness before disassembly. [Elektroda, MARIANOX5, post #17145324]
Is there a wiring diagram for the 2000–2006 Grand Vitara J20?
Yes. A forum member shared a schematic excerpt covering Grand Vitara J20 models from 2000–2006. Use it to cross‑check ECU pin numbers when tracing the cam sensor circuit. [Elektroda, pteter, post #17146025]
Where can I find a service manual for deeper troubleshooting?
A contributor linked a service resource for the SQ420 platform. It provides system descriptions and can supplement the shared schematic when validating sensor specs and timing procedures. "Here is the service" with the link was provided. [Elektroda, MARIANOX5, post #17146197]
My Vitara was flood‑damaged. What should I check before replacing more parts?
Inspect and remake sensor and ECU connectors, verify power, grounds, and the signal wire. In the case discussed, the car was flooded, connectors were refitted, the sensor was replaced, yet P0340 persisted until a mechanical timing error was fixed. [Elektroda, Raywood, post #17007148]
Is the crank sensor inductive on these engines, and what does it control?
Yes. The crankshaft sensor is inductive and is responsible for ignition. The poster notes similar behavior on Baleno 1.8 and earlier engines, highlighting platform commonality for diagnosis context. [Elektroda, MARIANOX5, post #17145525]
How do I test the cam sensor signal in three quick steps?
- Back‑probe the ECU cam signal pin with an oscilloscope or LED/diode probe.
- Crank the engine and observe a pulsing waveform or flashing LED.
- If no pulse, inspect the signal wire continuity and connector pins before suspecting the sensor. [Elektroda, Pawel wawa, post #17006988]
