B13CA — Left - Static curve lamp - Electric power supply

Causes

• Blown fuse or fusible link for left lighting circuit
• Open or shorted wiring in supply or ground to the left static curve lamp
• Corroded/damaged lamp connector or pins
• Failed left static curve lamp module or bulb/LED assembly
• Faulty Body Control Module / lighting control module output
• Water ingress or mechanical damage at the lamp or connector

Symptoms

• Left static curve lamp does not illuminate when expected (turning/low-speed cornering)
• Dashboard warning or lamp-out message
• Lamp flickers or works intermittently
• Other left-side lighting anomalies (dipped/side lamp affected)
• DTC B13CA stored in vehicle fault memory

What to check

• Scan vehicle and read all stored and pending fault codes; note freeze frame and related lighting codes
• Visually inspect left front lamp assembly, lens, and wiring harness for damage or water ingress
• Check fuses and fusible links for the lighting circuits
• Inspect and wiggle connectors at the lamp and BCM while observing lamp and scanner live data
• Measure battery voltage at the lamp connector with key ON and with lamp commanded ON
• Measure ground continuity from lamp ground pin to chassis (low ohms expected)

Signal parameters

• Expected supply voltage at lamp connector: ~11–14.5 V with engine running or key ON
• Ground resistance to chassis: typically
• Lamp current draw: varies by lamp type (LED assemblies typically 0.1–2 A; halogen higher) — compare with specification
• Control signal: may be steady 12 V or PWM-modulated when commanded; PWM frequency typically in the 100–500 Hz range for LED drivers
• No voltage on supply pin when fuse removed or BCM output disabled

Similar codes