OBD-II trouble code
P0209: Injector Circuit/Open - Cylinder 9
SAE J2012 APR2002: injector circuit/open, cylinder 9. The GRP01 injector-control rows that were checked run through cylinder 8 and do not print P0209. Order a ninth injector only after the diagram shows one.
Quick facts
- System
- Powertrain
- Category
- Fuel Injectors
- Severity
- Medium severity
- Drivable
- Usually safe to drive short-term
- Repair cost range
- $770 – $950 (one fuel injector replacement, parts and labor, RepairPal national average updated 3 September 2026; that page has no cylinder-9 line, and wiring is outside this pair)
- DIY difficulty
- Shop recommended
Browse every code in P0200–P0299, or start from the full code library.
What does P0209 mean?
SAE J2012 APR2002 names P0209 Injector Circuit/Open - Cylinder 9. In the same table, P0285 is cylinder 9 injector circuit low and P0286 is cylinder 9 injector circuit high. Section 3.1 defines Circuit/Open as a fixed value or no response, or as the general code used when low and high are also detected.
The 2007 GM file 07_GRP01_All Engines prints injector control-circuit rows for cylinders 1 through 8. A pass through those rows did not find a P0209 monitor, a 3 ms time, or a 6 ms time for cylinder 9. Do not extend cylinder 8's 3 ms open or no-load test to a ninth injector. The 2009 Cobalt chart ends at cylinder 4. The 2008 Envoy chart ends at cylinder 6. Volkswagen tips 01-20-02 and 97-18-02 end at P0204.
If this engine's service information has no cylinder 9 injector, the SAE name is not an instruction to build one. Engines that do have nine or more injectors use whatever numbering and driver that book prints. The electrical split, where the chart is a low-side or high-side driver, is still three results: open, short to ground, and short to voltage. Unplugging the injector and seeing the bias the chart expects does not prove a short. Continuity uses both ends disconnected and the ignition off. A short-to-voltage reading is taken with the module disconnected so the driver is not mistaken for the fault.
RepairPal's national injector average, updated 3 September 2026, does not publish a cylinder-9 line. The pair below is that national average for one injector replacement. It is not a quoted price for a ninth injector on an engine the page does not list. Depressurize with the published procedure before a line is opened. Do not apply 12 volts to a direct or common-rail injector.
Common causes
- A cylinder 9 control circuit open, with both ends disconnected and the ignition off
- A short to ground on that wire, injector unplugged and module disconnected
- A short to voltage that remains after the module is disconnected and that is not the chart's open-circuit bias
- A winding that fails the resistance this chart prints, measured with the injector unplugged
- A GRP01 3 ms or 6 ms figure copied from cylinders 1 through 8, which that sheet does not print for P0209
- A part ordered for an engine whose diagram has no ninth injector
- A module driver, after the three wire results are clear
Symptoms
- P0209 stored
- P0285 or P0286 when the calibration stores the low or high row
- No GRP01 time threshold to quote, because that sheet's injector-control rows stop at cylinder 8
- A ninth injector the diagram can point to, on an engine that has one
- A code on an engine that does not have nine injectors, which is a chart problem before it is a parts problem
Diagnostic steps
- 1.Open the injector diagram. Count the injectors. If nine is not there, stop and reread which code was actually stored.
- 2.Separate P0209 from P0285 and P0286.
- 3.Do not import the Cobalt lamp, the Envoy X104 step, the Volkswagen T8 part number, or the GRP01 millisecond times. Those documents do not list this code.
- 4.Ignition off, unplug the cylinder 9 injector the diagram names. Measure the winding against this vehicle's spec.
- 5.Open: continuity, both ends off, ignition off. Short to ground: wire to ground, module off the circuit. Short to voltage: key on, injector off, module off, compared with the disconnected voltage this chart prints.
- 6.Depressurize before the injector is removed. High-pressure fuel can penetrate skin. Do not crack a union to see if pressure remains.
- 7.If the injector is replaced, RepairPal's 3 September 2026 description removes the intake on the engines it covers and says the job is not DIY. That description is not a cylinder-count adder.
- 8.Verify with this calibration's monitor, not with a millisecond borrowed from GRP01 cylinder 8.
Repair cost
$770 – $950 (one fuel injector replacement, parts and labor, RepairPal national average updated 3 September 2026; that page has no cylinder-9 line, and wiring is outside this pair)
RepairPal's fuel injector replacement, updated 3 September 2026, averages $768–$953, rounded to $770–$950. Labor is $304–$446 and parts are $464–$507. The 2026 Hyundai Tucson line is $456–$604 and is outside the pair. No cylinder-9 line was on that national page. A ninth injector priced in this engine's parts book can sit outside the average. Wiring is not in the pair. Check-engine diagnosis is $125–$183 and is separate.
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DIY vs shop
Leave this one to a qualified shop. The barrier here is high-pressure fuel components, where residual pressure remains after shutdown and escaping fuel can penetrate skin. DIY attempts often produce a more expensive problem than the original code.