Six-, eight- and some five-cylinder engines can lose cylinder 5 to an injector circuit fault. The engine runs rough, and power drops. A P0205 code means the engine computer found a problem in the fuel injector circuit for cylinder 5.
This guide explains how to find cylinder 5 on your engine, what causes the fault and how to test the circuit.
P0205 Code Breakdown
Every OBD-II code follows the same five-character pattern set by the SAE J2012 standard. Each character narrows down which system has the fault. This table shows what each part of the code tells you.
| Character | Meaning | What It Tells You |
|---|---|---|
| P | Powertrain | The fault is in the engine or transmission systems. |
| 0 | Generic (SAE) code | The definition is the same on every OBD-II vehicle. |
| 2 | Fuel and air metering (injector circuit) | The fault involves the fuel injectors and their circuits. |
| 05 | Specific fault | Injector Circuit Malfunction, Cylinder 5 |
What the P0205 Code Means
The SAE J2012 standard defines the P0205 code as Injector Circuit Malfunction, Cylinder 5. On most port injection engines, the injector gets battery voltage from a fuse or relay. The powertrain control module (PCM) opens it by grounding the control wire for a few milliseconds at a time.
Each injector has its own driver inside the PCM, and the PCM watches that circuit every time it switches. When the cylinder 5 circuit shows the wrong voltage, such as an open, a short or a missing voltage spike when the injector closes, the code sets.
Only engines with five or more cylinders have cylinder 5. On V6 and V8 engines, its bank and position depend on the manufacturer. Some V engine injectors sit under the intake manifold, which makes access harder. Check your service manual for the layout.
Symptoms of a Cylinder 5 Injector Fault
With one injector out, the engine runs on fewer cylinders. Common signs of a P0205 code include:
- Check engine light on, sometimes flashing
- Rough idle and shaking
- Misfire code P0305 for cylinder 5
- Hesitation and loss of power
- Poor fuel economy
- Fuel smell from the exhaust
Common Causes of the P0205 Code
The fault can be in the injector, the wiring or the PCM. These are the usual causes:
- Loose or corroded injector connector. Heat and oil leaks weaken the pins.
- Broken or chafed control wire. Wiring near the intake can rub through.
- Open injector coil. The injector no longer responds.
- Shorted injector coil. It draws too much current and can harm the PCM driver.
- Lost power feed. A broken wire between the fuse and this injector.
- Failed PCM injector driver. Less common, but possible.
How to Diagnose the P0205 Code
You need a scan tool, a digital multimeter, a noid light and the wiring diagram. Start by confirming which cylinder is cylinder 5 on your engine.
Inspect the Connector and Wiring
Find the cylinder 5 injector and check its connector. Make sure it is fully seated and locked. Look for broken tabs, corrosion, oil inside the plug and wires rubbing on brackets or the intake.
Check Power and Control
Unplug the injector. With the key on, one connector pin should show battery voltage. Then plug in a noid light and crank the engine. A steady flash means the PCM is pulsing the injector. No flash points to a broken control wire or a PCM driver fault.
Measure the Injector
Measure resistance across the injector’s two terminals. Most high-impedance port injectors read about 11 to 18 ohms. Compare it with the other injectors. An open, a near-zero reading or a value far from the rest means the injector is bad.
How to Fix the P0205 Code
Repair the fault your tests found. Then clear the codes and road test the vehicle.
- Reseat or replace the connector if it is loose or corroded.
- Repair broken or chafed wiring with solder and heat shrink tubing.
- Replace the cylinder 5 injector if its resistance is out of spec.
- Fix oil leaks that soak the injector wiring.
- Repair or replace the PCM only after the wiring and injector test good.
On port injection engines, swapping the injector with a neighboring cylinder is a quick check. If the code moves with the injector, the injector is bad. If it stays on cylinder 5, look at the wiring and PCM.
What Repairs Cost
The cost of a P0205 code repair depends on what failed and how easy the injector is to reach. This table shows typical ranges.
| Repair | DIY Cost | Typical Shop Cost |
|---|---|---|
| Connector or pigtail | $15 to $40 | $100 to $200 |
| Wiring repair | $10 to $30 | $100 to $300 |
| Port fuel injector | $40 to $150 | $150 to $400 |
| Direct injection injector | $100 to $400 | $300 to $900 |
| PCM repair or replacement | $200 to $800 | $500 to $1,500 |
Is It Safe to Drive with a P0205 Code?
It is best to avoid it. The misfire sends unburned fuel and air through the exhaust, which can overheat the catalytic converter and ruin it.
The engine also loses power and may stall. If the check engine light flashes, stop driving and have the vehicle towed.
Related Codes
These codes often show up with this one or point to the same system:
| Code | Meaning |
|---|---|
| P0202 | Injector Circuit Malfunction, Cylinder 2 |
| P0203 | Injector Circuit Malfunction, Cylinder 3 |
| P0204 | Injector Circuit Malfunction, Cylinder 4 |
| P0206 | Injector Circuit Malfunction, Cylinder 6 |
| P0207 | Injector Circuit Malfunction, Cylinder 7 |
Getting Cylinder 5 Firing Again
A P0205 code means the PCM found a fault in the cylinder 5 injector circuit. Loose connectors, damaged wires and failed injectors cause most cases.
- Confirm which cylinder is cylinder 5.
- Inspect the connector and wiring.
- Check power and use a noid light.
- Measure injector resistance and compare it with the others.
Frequently Asked Questions
Which Engines Have a Cylinder 5?
Five-cylinder, six-cylinder and eight-cylinder engines all have one. On V engines, cylinder 5 can be on either bank, depending on the manufacturer. A four-cylinder engine cannot set the P0205 code, so a scan tool showing it on one points to a PCM or software issue.
Why Is the Cylinder 5 Injector Hard to Reach?
On many V6 and V8 engines, the injectors sit under the upper intake manifold. Reaching cylinder 5 may mean removing the plenum and several hoses. That extra labor raises the shop cost, even though the injector itself is not expensive.
Can a Bad Injector Driver Cause the P0205 Code?
Yes. The PCM uses a separate driver for each injector. If the cylinder 5 driver fails, the injector gets no ground signal. A shorted injector can damage the driver, so test the injector resistance before replacing the PCM.
Will the Engine Run with the P0205 Code?
It usually runs, but rough. Cylinder 5 may get no fuel, so the engine shakes and loses power. A P0305 misfire code often appears too. Drive gently and get it fixed soon to protect the catalytic converter.