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P0135BuickBuick Enclave HubAll Buick P0135Low to Medium Severity

P0135 on Buick Enclave: Fix & DLC Location

Factory diagnostic troubleshooting wire for fault code P0135 (O2 Sensor Heater Circuit Malfunction (Bank 1, Sensor 1)) specifically on the Buick Enclave (2020–2026, 3.6L V6 (310HP) / 2.5L Turbo 4-Cyl (328HP)).

Buick Enclave
DIY Parts Estimate
$80 - $240 (DIY Sensor: $45)
Enclave OEM Fitment
Shop Labor Quote
$180 – $380
Based on $115/hr labor
Drivability Status
Drivable (Short Trip)
Low to Medium urgency level
Est. DIY Time
45 – 90 Min
Basic hand tools
Check P0135 On Another Buick Model:
Buick Enclave

1. Symptoms of P0135 on Buick Enclave

When the Engine Control Module (ECM/PCM) on your Buick Enclave (3.6L V6 (310HP) / 2.5L Turbo 4-Cyl (328HP)) logs fault code P0135, drivers commonly observe:

Check Engine Light on on Buick Enclave (3.6L V6 (310HP) / 2.5L Turbo 4-Cyl (328HP))
Slightly increased fuel consumption on short trips on Buick Enclave (3.6L V6 (310HP) / 2.5L Turbo 4-Cyl (328HP))
Failed state emissions inspection on Buick Enclave (3.6L V6 (310HP) / 2.5L Turbo 4-Cyl (328HP))
Buick Enclave OBD-II Port Location
The 16-pin diagnostic connector is located Driver lower knee bolster panel. Plug in your scan tool to verify freeze-frame sensor values.

2. Most Likely Causes on Buick Enclave

Historical warranty claims and technical repair bulletins for Buick Enclave point to the following failure distribution:

55%
Burnt-out internal heating element in upstream oxygen sensor (Buick OEM Part)
25%
Blown O2 sensor heater fuse (Buick OEM Part)
12%
Melted or damaged sensor wiring near exhaust manifold (Buick OEM Part)
8%
Excessive circuit resistance (Buick OEM Part)

3. Step-by-Step DIY Repair Guide for Buick Enclave

01
Check the Heater Fuse

Locate the under-hood fuse box and test the O2 sensor heater fuse with a multimeter or test light. on the Buick Enclave equipped with 3.6L V6 (310HP) / 2.5L Turbo 4-Cyl (328HP).

02
Measure Sensor Heater Resistance

Unplug the Bank 1 Sensor 1 connector and test resistance between the two heater pins (typically 3 to 15 ohms). on the Buick Enclave equipped with 3.6L V6 (310HP) / 2.5L Turbo 4-Cyl (328HP).

03
Replace Upstream O2 Sensor

Use an O2 sensor socket wrench to remove the old sensor from the exhaust manifold and install an OEM-spec replacement with anti-seize on the threads. on the Buick Enclave equipped with 3.6L V6 (310HP) / 2.5L Turbo 4-Cyl (328HP).

Other Common Fault Codes on Buick Enclave

Frequently diagnosed powertrain, emissions, and sensor trouble codes logged on the Buick Enclave:

4. Buick Enclave P0135 FAQs

What causes code P0135 to trigger on a Buick Enclave?

On the Buick Enclave (3.6L V6 (310HP) / 2.5L Turbo 4-Cyl (328HP)), P0135 is most frequently caused by Burnt-out internal heating element in upstream oxygen sensor or Blown O2 sensor heater fuse.

Where is the OBD-II port located on my Buick Enclave?

On the Buick Enclave, the 16-pin DLC diagnostic connector is located Driver lower knee bolster panel. Plug in any standard OBD-II scanner with the ignition in the ON position to read freeze-frame parameters.

Can I safely drive my Buick Enclave with code P0135?

Yes, vehicle is safe to drive, but will stay in open-loop mode longer upon startup. Given that P0135 carries a Low to Medium severity rating, we advise avoiding heavy towing or aggressive throttle inputs until sensor readings are verified.