P0273 on 2009-2014 Chevrolet Traverse: Cylinder 5 Injector Circuit Low Causes & Fixes

What's Unique About the 2009-2014 Chevrolet TRAVERSE

The 3.6L V6 engine used in the first-generation Chevrolet Traverse and its platform mates (GMC Acadia, Buick Enclave, Saturn Outlook) is known for a specific wiring issue. A GM Technical Service Bulletin (TSB #PIP4924D) directly addresses that the fuel injector wiring harness can rub through where it passes near or under the intake plenum, against valve cover bolts, or the side of the cylinder head. This makes a harness inspection a critical first step, often more so than on other vehicles where the injector itself is the primary suspect.

Diagnostic Flowchart

Tap your situation to follow the diagnostic path that matches what you're seeing on this vehicle.

Symptoms You May Notice

• Check Engine Light is on
• Rough or shaky idle
• Engine misfire, which may be audible as a popping or tapping sound
• Poor acceleration and hesitation
• Reduced fuel economy
• Engine may stall

Most Likely Causes

1. Chafed/Damaged Fuel Injector Wiring Harness 🔴 High Probability → Shop Engine Wiring Harness As documented in TSB #PIP4924D, the harness routing on the 3.6L V6 can lead to it rubbing against the intake plenum, valve cover bolts, fuel lines, or the side of the cylinder head, causing a short to ground. This is a very common failure point for this specific platform.
   How to confirm: Visually inspect the entire length of the fuel injector harness, paying close attention to contact points with the engine, especially under the intake plenum. Look for bare wires, melted plastic loom, or obvious signs of rubbing. Use a multimeter to check for a short to ground on the control wire for the cylinder 5 injector.
   Typical fix: Repair the damaged section of wire. This involves cutting out the bad section, splicing in a new piece of wire, soldering the connections, and protecting the repair with heat-shrink tubing. Reroute the harness slightly or add protective conduit (split-loom tubing) to prevent future rubbing. Ensure the harness is properly secured away from sharp edges.
   Est. part cost: $5-$25
2. Faulty Cylinder 5 Fuel Injector 🟡 Medium Probability → Shop Fuel Injector Injectors can fail electrically (internal short or open circuit) or become clogged over time, which is a common issue on any vehicle. While less common than the harness issue on this platform, it is the next logical component to fail.
   How to confirm: After confirming the wiring is good, swap the cylinder 5 fuel injector with one from another cylinder (e.g., cylinder 3). Clear the codes and drive the vehicle. If the code changes to P0267 (Cylinder 3 Injector Circuit Low), the injector is faulty. You can also test the injector's resistance with a multimeter and compare it to the other injectors. The expected resistance is critically different between 2009-2011 LLT engines (~12 Ohms) and 2012-2014 LFX engines (~1.5 Ohms).
   Typical fix: Replace the faulty fuel injector. It is often recommended to replace all fuel injector seals at the same time. Given the labor to access the injectors, some owners choose to replace all injectors on that bank at once.
   Est. part cost: $70-$150
3. Corroded or Loose Injector Connector ⚪ Low Probability
   How to confirm: Unplug the connector at the cylinder 5 injector and inspect the terminals for corrosion (green or white powder) or damage. Ensure it clicks securely back into place. A broken locking tab can cause a poor connection over time.
   Typical fix: Clean the terminals with electrical contact cleaner. If the connector is damaged or the locking tab is broken, a new pigtail connector will need to be spliced onto the harness.
   Est. part cost: $10-$30

Rare But Worth Checking

• Faulty Engine Control Module (ECM): → Shop Engine Control Module (ECM) This is the least likely cause. The ECM's internal driver circuit for the injector can fail, but all other possibilities, especially wiring, must be exhaustively ruled out first.

Diagnosis Steps

1. Scan the ECM for all stored trouble codes. Note if any other injector or misfire codes are present.
2. Perform a thorough visual inspection of the fuel injector wiring harness, specifically looking for chafing against the engine as described in TSB #PIP4924D. This may require removing the engine cover and intake plenum for full access.
3. Disconnect the harness at the cylinder 5 injector. Use a noid light to verify that the ECM is sending a pulse signal to the injector while cranking the engine.
4. With the key on and engine off, use a multimeter to check for battery voltage on the power wire at the injector connector.
5. Check for continuity on the control wire between the injector connector and the ECM connector (Pin 18 on connector X2). Also, check this wire for any short to ground.
6. If wiring and signal are confirmed good, test the resistance of the fuel injector itself (disconnect it first) and compare it to the other injectors. A significant difference indicates a faulty injector. Ensure you use the correct specification for your engine year (LLT vs LFX).
7. As a final confirmation, swap the cylinder 5 injector with another one (e.g., from cylinder 3). If the fault code follows the injector to its new cylinder (now showing P0267), the injector is confirmed bad.

Parts You'll Likely Need

• Fuel Injector (OEM #12638530 (for 3.6L LLT, 2009-2011), 12663380 (for 3.6L LFX, 2012-2014)) — If the wiring harness is intact, the injector itself is the next most likely component to have failed electrically. Part numbers differ between the LLT and LFX engines.
  Trusted brands: ACDelco, Bosch, Standard Motor Products
  OEM price range: $100-$160
  Aftermarket price range: $50-$120
• Fuel Injector Wiring Harness Pigtail (OEM #ACDelco PT2652 (verify connector match)) — Needed if the electrical connector at the injector is broken or corroded beyond cleaning. The locking tab often becomes brittle and breaks.
  Trusted brands: Dorman, ACDelco, Carquest
  OEM price range: $25-$40
  Aftermarket price range: $10-$20
• Split Loom Conduit / Electrical Tape — Essential for protecting the repaired wire and preventing the harness from chafing again in the future.
  Trusted brands: 3M, Dorman
  OEM price range: $5-$15
  Aftermarket price range: $5-$15

Related Codes That Often Appear With This One

• P0305 — This code means 'Cylinder 5 Misfire Detected'. A faulty injector circuit (P0273) prevents proper fueling, which directly causes the cylinder to misfire.
• P0205 — This is a general malfunction code for the cylinder 5 injector circuit and may appear alongside the more specific P0273.
• P0261, P0264, P0267, P0270, P0276 — These are the 'Circuit Low' codes for the other cylinders. If multiple injector codes are present, it strongly suggests a widespread wiring harness issue rather than multiple failed injectors, as noted in TSB #PIP4924D.

Technical Service Bulletins (TSBs) & Recalls

• PIP4924D: Mentions that misfires and various injector codes (P0201-P0206, P0261-P0277, etc.) can be caused by the fuel injector wiring harness rubbing through on engine components. Recommends inspection and repair/replacement of the harness.

Platform-Specific Known Issues

• TSB #PIP4924D explicitly warns that the fuel injector wiring harness can rub through against engine components like the intake plenum or valve cover bolts, causing various injector circuit codes, including P0273.
• Owner experiences on forums like traverseforum.com frequently confirm the wiring harness as the culprit. A common chafing spot is where the harness wraps around the rear cylinder head (Bank 1), which is tight and prone to vibration.
• Cylinder 5 is on Bank 1 (the firewall side), which is more difficult to access and inspect than Bank 2 (the radiator side).

Mechanic-Grade Diagnostic Values

• Fuel Injector Resistance (2009-2011 3.6L LLT Engine) — expected: 11.8 - 12.6 Ohms. Failure: A reading of 0 ohms (short), infinity/OL (open), or significant deviation from this range indicates a failed injector.
• Fuel Injector Resistance (2012-2014 3.6L LFX Engine) — expected: 1.2 - 1.8 Ohms. Failure: A reading outside this narrow range indicates an internal injector fault. Note the significant difference from the earlier LLT engine.
• Injector Circuit Voltage (Key On, Engine Off) — expected: 11.5V - 12.5V on the power feed wire at the injector connector.. Failure: A reading below 10V suggests excessive resistance or a short in the wiring harness or connector.
• Wiring Harness Continuity — expected: < 0.2 Ohms. Failure: Resistance greater than 0.2 Ohms on the control or power wire (when tested end-to-end) indicates a compromised wire or poor connection.

Scan Tool Commands That Help

• GM GDS2 (or equivalent high-end scan tool): Injector Balance Test / Automated Fuel Injector Balance Test — This bidirectional test can be used after confirming wiring integrity. The scan tool commands the ECM to disable each injector one by one and measures the resulting change in fuel rail pressure or engine RPM. A cylinder that shows little or no change when its injector is disabled points to a non-functioning injector, helping confirm a bad injector without physically swapping it.

Wiring & Ground Locations

• Injector 5 Control Wire @ ECM — Pin 18 of the X2 connector on the Engine Control Module (ECM). The wire is typically Brown with a White stripe.. This is the specific control wire for the cylinder 5 injector. Testing for continuity from the injector connector to this pin is the definitive way to confirm if the wire is broken (open) or shorted to ground somewhere in the harness.
• G107 — On the upper left (driver's) side of the engine block for the 3.6L engine.. This is a primary engine ground. A poor or corroded connection here can affect the ECM and its sensor readings, potentially causing erratic signals or voltage-related codes.
• G101 (Engine Block Ground) — Typically located on the front of the engine block, near the starter or on a lower corner.. A main engine ground point. While G107 is more directly cited for the LFX, ensuring all major block grounds are clean and tight is crucial for resolving any electrical fault, including injector circuit issues.
• X160 / X161 — Multi-way harness connectors located at the rear of the intake manifold.. These are the main connectors for the fuel injector harness. Service manuals direct technicians to test circuits at these points to isolate faults between the ECM and the injectors, which can save the labor of removing the intake manifold for initial testing.

Real Owner Repair Stories

• YouTube Channel 'Normal's Garage' (2014 Chevy Impala 3.6L (LFX Engine, same family as Traverse)) — Check engine light with misfire codes for multiple cylinders.
  ❌ Tried (didn't work) Initial visual scan was confusing due to multiple codes.
  ✅ What actually fixed it The technician tested the resistance of each injector from the main harness connector. The injector for cylinder #3 read completely open (OL). After removing the intake manifold to access the injector directly, a direct resistance test on the injector confirmed it was internally open. Replacing the single faulty fuel injector resolved the issue.

OEM Part Supersession History

• 12638530 → 12669384 — Standard part evolution, potentially for improved reliability or manufacturing process.
  Heads up: This part is for the high-impedance LLT engine only and is not compatible with the 2012+ LFX engine.

Model Year Variations Within This Range

• 2009-2011: These models use the 3.6L LLT V6 engine. They are equipped with high-impedance fuel injectors (~12 Ohms), an aluminum intake manifold, and a Bosch ECM. The correct injector part number is 12638530 (or its successor).
• 2012-2014: These models use the updated 3.6L LFX V6 engine. They have low-impedance fuel injectors (~1.5 Ohms), a composite intake manifold, integrated exhaust manifolds, and a Delphi ECM. Using the resistance specification from the earlier LLT engine will lead to a certain misdiagnosis.