B1201 on Cadillac Lyriq
Factory diagnostic protocol and troubleshooting wire for fault code B1201 specifically for the Cadillac Lyriq (2023–2026, Ultium Dual Motor AWD (500HP / 450 lb-ft) / Single Motor RWD (340HP)).
1. Symptoms of B1201 on Cadillac Lyriq
When the Engine Control Module (ECM/PCM) on your Cadillac Lyriq (Ultium Dual Motor AWD (500HP / 450 lb-ft) / Single Motor RWD (340HP)) logs fault code B1201, drivers commonly observe:
2. Most Likely Causes on Cadillac Lyriq
Historical warranty claims and technical repair bulletins for Cadillac Lyriq point to the following failure distribution:
3. Step-by-Step DIY Repair Guide for Cadillac Lyriq
Connect an OBD-II scan tool and record freeze frame sensor telemetry for code B1201 to note engine RPM, load, and voltage when the fault triggered. on the Cadillac Lyriq equipped with Ultium Dual Motor AWD (500HP / 450 lb-ft) / Single Motor RWD (340HP).
Inspect the electrical connector and wiring harness related to B1201 for chafing, corrosion, moisture, or pin push-out. on the Cadillac Lyriq equipped with Ultium Dual Motor AWD (500HP / 450 lb-ft) / Single Motor RWD (340HP).
Measure circuit voltage supply (12V B+ or 5V reference) and sensor/actuator resistance according to factory repair manual specifications. on the Cadillac Lyriq equipped with Ultium Dual Motor AWD (500HP / 450 lb-ft) / Single Motor RWD (340HP).
Install a new OEM-grade replacement part, torque fasteners to factory spec, and ensure electrical locking tabs click firmly. on the Cadillac Lyriq equipped with Ultium Dual Motor AWD (500HP / 450 lb-ft) / Single Motor RWD (340HP).
Clear all stored DTCs from vehicle memory and perform an OBD-II drive cycle to confirm the diagnostic monitor resets to 'Ready'. on the Cadillac Lyriq equipped with Ultium Dual Motor AWD (500HP / 450 lb-ft) / Single Motor RWD (340HP).
Equipment for Diagnosing Cadillac Lyriq (B1201)
Cadillac Lyriq OEM Replacement Sensor
Direct-fit replacement assembly engineered to OEM tolerances for Cadillac Lyriq.
AstroAI Auto-Ranging Digital Multimeter
Essential for testing 0.1V–5.0V sensor reference signals, ground continuity (<0.20Ω), and harness resistance.
BlueDriver Bluetooth Pro OBDII Scan Tool
Reads and clears enhanced codes (ABS, Airbag, Transmission, Engine) & live freeze-frame telemetry on phone.
Other Common Fault Codes on Cadillac Lyriq
Frequently diagnosed powertrain, emissions, and sensor trouble codes logged on the Cadillac Lyriq:
4. Cadillac Lyriq B1201 FAQs
What causes code B1201 to trigger on a Cadillac Lyriq?
On the Cadillac Lyriq (Ultium Dual Motor AWD (500HP / 450 lb-ft) / Single Motor RWD (340HP)), B1201 is most frequently caused by Open circuit in fuel sender wiring or Worn in-tank fuel level sensor contacts.
Where is the OBD-II port located on my Cadillac Lyriq?
On the Cadillac Lyriq, the 16-pin DLC diagnostic connector is located Under driver steering column beneath knee bolster. Plug in any standard OBD-II scanner with the ignition in the ON position to read freeze-frame parameters.
Can I safely drive my Cadillac Lyriq with code B1201?
Yes. Fuel gauge inaccurate. Given that B1201 carries a Low severity rating, we advise avoiding heavy towing or aggressive throttle inputs until sensor readings are verified.