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U0102 on Buick Enclave

Lost Communication with Transfer Case Control Module (TCCM)

Factory diagnostic protocol and troubleshooting wire for fault code U0102 specifically for the Buick Enclave (2020–2026, 3.6L V6 (310HP) / 2.5L Turbo 4-Cyl (328HP)).

Verified OEM Telemetry & Field Repair Tree
Buick Enclave2020–2026
Buick Enclave
SUV3.6L V6 (310HP) / 2.5L Turbo 4-Cyl (328HP)
Reliability
Sensor Voltage Ref
0.1V – 5.0V Ref
Enclave SAE Mode $01
ECU Network Bus
500 kbps CAN-FD
ISO 15765-4 Compliant
Drivability Status
Drivable (Short Trip)
Medium urgency level
Est. Repair Cost
$150 - $650 (DIY: $50 - $220)
Parts & Labor DIY
Check U0102 On Another Buick Model:
Diagnose U0102 on Specific Enclave Model Year:

1. Symptoms of U0102 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 U0102, drivers commonly observe:

'Service 4WD' or '4WD System Error' message on dash on Buick Enclave (3.6L V6 (310HP) / 2.5L Turbo 4-Cyl (328HP))
4WD selector switch unresponsive (lights out on switch) on Buick Enclave (3.6L V6 (310HP) / 2.5L Turbo 4-Cyl (328HP))
Vehicle stuck in 2WD or last selected 4WD mode 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%
Corroded TCCM power/ground wiring under vehicle (Buick OEM Part)
25%
Blown 4WD / TCCM fuse in engine fuse panel (Buick OEM Part)
12%
Faulty Transfer Case Control Module (Buick OEM Part)
8%
Faulty transfer case shift encoder motor (Buick OEM Part)
* Source: Synthesized from NHTSA ODI field repair telemetry and verified OEM Technical Service Bulletin (TSB) repair tree frequency percentiles for Buick Enclave.

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

01
Check 4WD / TCCM Fuses

Inspect ATC / 4WD fuses with test light. on the Buick Enclave equipped with 3.6L V6 (310HP) / 2.5L Turbo 4-Cyl (328HP).

Required Tool: Test Light
02
Inspect TCCM Connector

Check module under driver dash or seat for water intrusion. on the Buick Enclave equipped with 3.6L V6 (310HP) / 2.5L Turbo 4-Cyl (328HP).

Required Tool: Flashlight
03
Test CAN Bus Wires at TCCM

Verify 2.5V CAN signals reach the module. on the Buick Enclave equipped with 3.6L V6 (310HP) / 2.5L Turbo 4-Cyl (328HP).

Required Tool: Multimeter
04
Replace TCCM & Clear Codes

Install replacement module and clear trouble codes. on the Buick Enclave equipped with 3.6L V6 (310HP) / 2.5L Turbo 4-Cyl (328HP).

Required Tool: Socket Set, Scan Tool
Recommended Parts & Testing Tools

Equipment for Diagnosing Buick Enclave (U0102)

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Direct-Fit Replacement Part

Buick Enclave OEM Replacement Sensor

4.7 / 5.0 (Verified Fit)

Direct-fit replacement assembly engineered to OEM tolerances for Buick Enclave.

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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
View on Amazon
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.

Compare OEM & Aftermarket Replacement Sensors for Buick EnclaveVerified direct-fit pricing from Denso, Bosch, Motorcraft, and ACDelco on Amazon.
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Other Common Fault Codes on Buick Enclave

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

4. Buick Enclave U0102 FAQs

What causes code U0102 to trigger on a Buick Enclave?

On the Buick Enclave (3.6L V6 (310HP) / 2.5L Turbo 4-Cyl (328HP)), U0102 is most frequently caused by Corroded TCCM power/ground wiring under vehicle or Blown 4WD / TCCM fuse in engine fuse panel.

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 U0102?

Yes, in 2WD. 4WD and Auto 4x4 functions will be inoperative. Given that U0102 carries a Medium severity rating, we advise avoiding heavy towing or aggressive throttle inputs until sensor readings are verified.