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P0202 on GMC: Symptoms, Causes & Fix

Injector Circuit Malfunction - Cylinder 2

Official technical diagnostic wire for fault code P0202 specifically affecting GMC vehicles (Sierra 1500, Yukon, Acadia, Canyon, Terrain).

Sensor Voltage Ref
0.1V – 5.0V Ref
GMC Factory Standard
CAN Bus Speed
500 kbps CAN-FD
ISO 15765-4 Diagnostic Bus
Drivability Status
Not Recommended
Critical urgency level
Est. Repair Cost
$150 - $550 (DIY: $40 - $180)
Parts & Labor DIY
Model-Specific Diagnostic Wires

Select Your GMC Model for P0202:

5 Models Available

1. Common Symptoms on GMC Vehicles

When GMC Engine Control Modules (ECM) trigger fault code P0202, drivers typically report:

Check Engine Light flashing on GMC Powertrains
Violent engine vibration under load on GMC Powertrains
Stumbling idle and severe power drop on GMC Powertrains
Accompanying code P0302 on GMC Powertrains

2. Root Causes on GMC Engines

Historical diagnostic claims across GMC engines point to the following failure distribution:

55%
Cylinder 2 fuel injector internal coil failure (GMC OEM Part)
25%
Broken wiring or corroded connector pin on Cylinder 2 harness (GMC OEM Part)
12%
Blown injector power feed fuse (GMC OEM Part)
8%
PCM injector driver circuit failure (GMC OEM Part)

3. Step-by-Step Fix Protocol for GMC

01
Measure Cylinder 2 Injector Resistance

Measure resistance across injector 2 terminals. Compare to Cylinder 1 and 3 (spec: 12–16 ohms). on GMC engines.

Required Tool: Digital Multimeter
02
Test for 12V Power and Ground Pulse

Check for 12V on power wire and verify ground pulsing using a noid light while cranking. on GMC engines.

Required Tool: Noid Light, Multimeter
03
Replace Cylinder 2 Fuel Injector

Depressurize fuel system, lift rail, swap injector, lube new O-rings, and reinstall rail. on GMC engines.

Required Tool: Socket Set, Fuel Line Disconnect Tool
04
Clear Codes and Verify Smooth Running

Clear DTC memory and monitor misfire counters on live data. on GMC engines.

Required Tool: OBD-II Scanner
Recommended Parts & Testing Tools

Equipment for Diagnosing GMC (P0202)

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Direct-Fit Replacement Part

GMC OEM Replacement Sensor

4.7 / 5.0 (Verified Fit)

Direct-fit replacement assembly engineered to OEM tolerances for GMC.

$45 – $95 Prime
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Sensor Signal Voltage Meter

AstroAI Auto-Ranging Digital Multimeter

4.6 / 5.0 (Best Seller)

Essential for testing 0.1V–5.0V sensor reference signals, ground continuity (<0.20Ω), and harness resistance.

$29.99 Prime
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Top Mobile OBD-II Scanner

BlueDriver Bluetooth Pro OBDII Scan Tool

4.7 / 5.0 (50,000+ Reviews)

Reads and clears enhanced codes (ABS, Airbag, Transmission, Engine) & live freeze-frame telemetry on phone.

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4. GMC P0202 Frequently Asked Questions

What does code P0202 mean on a GMC?

On GMC vehicles, P0202 indicates that the Engine Control Module (ECM) detected injector circuit malfunction - cylinder 2. This typically points to Cylinder 2 fuel injector internal coil failure or Broken wiring or corroded connector pin on Cylinder 2 harness.

Can I continue driving my GMC with code P0202?

No. Cylinder 2 is completely disabled by an electrical circuit fault, causing hard misfires. Because this code carries a Critical severity rating on GMC powertrains, we recommend scanning live data values promptly to prevent secondary damage.

How much does it cost to fix code P0202 on a GMC?

Estimated DIY parts cost ranges from $150 - $550 (DIY: $40 - $180), while professional shop repairs at an authorized GMC dealership or independent specialist typically range from $180 to $380 including diagnostic labor.