P0206

Code

Generic P — Powertrain

Cylinder 6 Injector A Circuit

Brand: Generic

Type: P — Powertrain

Views: UK: 44 EN: 53 RU: 48

AI status

Completed

ready

Completed 100%

Page language: EN

Causes

Open or shorted wiring between ECM and cylinder 6 injector
Poor or corroded connector at the injector or ECM
Failed or stuck injector (electrical or mechanical)
Blown fuse or faulty power feed/relay to injectors
Faulty ECM/PCM injector driver circuit
Aftermarket parts or recent repairs with incorrect wiring

Symptoms

Check Engine Light (MIL) illuminated
Rough idle or misfire localized to cylinder 6
Reduced engine power, hesitation or stumbling under load
Poor fuel economy and increased emissions
Possible hard starting or stumble during acceleration

What to check

Retrieve trouble codes and freeze frame data with a scan tool; note freeze frame and readiness
Visually inspect injector harness, connector, and pins at cylinder 6 for corrosion, damage or oil intrusion
Check for any blown fuses or failed injector relay that supplies fuel injectors
Backprobe injector connector with key ON to confirm reference voltage/power is present
Measure injector coil resistance and compare to manufacturer spec
Use a noid light or scan tool to confirm injector is being pulsed when commanded

Signal parameters

Typical injector coil resistance: high-impedance 12–16 Ω, low-impedance 2–5 Ω (check OEM spec for exact value)
Reference supply: battery voltage (~B+) present at injector power pin with key ON
Driver output: ECM switches injector to ground; voltage at driver pin should drop near 0 V when commanded
Pulse width: typical 1–5 ms at idle; varies with load and RPM (scan tool will show pulse width)
Duty cycle: low at idle, increases with load; near 100% only at high demand
Oscilloscope waveform: sharp ground-side switching edges; look for missing pulses, shorted waveform, or noisy signal

Diagnostic algorithm

Confirm code and record freeze frame data. Clear codes and attempt to reproduce.
Perform a visual inspection of wiring and connectors at cylinder 6 injector and ECM for obvious damage, corrosion or oil intrusion.
With ignition OFF, unplug the injector connector and inspect pins; check for bent or pushed-out terminals.
Measure injector coil resistance at the injector pins; compare to OEM spec. Replace injector if open or out-of-spec.
With key ON (engine OFF) backprobe the connector to verify battery voltage on the power feed circuit. If no voltage, check fuse/relay/power distribution.
Command the injector ON using a scan tool while monitoring the connector with a noid light or oscilloscope to confirm pulsing and waveform shape.
While commanding the injector, measure voltage at the driver pin; it should switch to near ground when energized. If it stays at battery, suspect driver open; if stuck at ground, suspect short to ground.
Check continuity between the injector connector and the ECM injector driver pin; inspect for short to battery or ground and for high resistance/opens.
Swap the suspect injector with a known good injector of the same type. If the code or misfire follows the injector, replace the injector.
If wiring and injector test good but code persists, inspect ECM connector and grounds. Repair damaged wiring or connector terminals as needed.
As a last step, if all wiring and injector tests are good and fault remains, consider ECM/PCM driver failure and consult manufacturer procedures for ECM testing/replacement.

Likely causes

Damaged connector or wiring (broken wire, pin corrosion, rodent damage)
Injector shorted internally or open (failed injector coil)
Poor pin contact at injector harness connector
Injector fuse/relay or shared power feed open
ECM driver fault (less common) or PCM software/firmware issue

Fault status

⚠️ Status

P0206 - Cylinder 6 Injector A Circuit: ECM detected abnormal electrical condition (open, short, excessive/insufficient current or voltage) in the injector circuit for cylinder 6.

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 1.0-3.0 hours