B19B2 – Right parking lamp/DRL fault – short to positive or open circuit (Mercedes-Benz)

B19B2 means the right parking lamp or right DRL may not work, or it may act erratically. You may also lose a front corner light that other drivers rely on to see you. According to Mercedes-Benz factory diagnostic data, this code indicates a right parking lamp/DRL fault caused by a short to positive or an open circuit. On a Sprinter 907, the body electronics monitor that lamp output for correct current flow and circuit behavior. The code does not prove the lamp unit failed. It points you to a circuit condition that the control module detected while commanding the right parking lamp/DRL on or off.

B19B2 Quick Answer

This Mercedes-Benz B19B2 code sets when the body control system sees the right parking lamp/DRL circuit as open or shorted to battery positive. Expect a right-side DRL/parking lamp outage or abnormal brightness until you confirm wiring, connector, bulb/LED module, and output stage behavior.

What Does B19B2 Mean?

Official definition: “Right parking lamp/DRL fault – short to positive or open circuit.” In plain terms, the control module tried to operate the right parking lamp/DRL and decided the circuit did not behave correctly. In practice, that often shows up as the right DRL/parking lamp staying off, staying on, flickering, or displaying a “lamp defective” message.

What the module actually checks: the Mercedes-Benz body electronics do not “look” at the bulb visually. The module monitors the commanded output and the electrical response it expects from that load. It checks for an open circuit (no current flow or no load signature). It also checks for a short to positive (the output line shows battery voltage when it should not, or it backfeeds power). Why that matters: you must prove whether the fault sits in the lamp assembly, the harness, the connector, or the module output stage before replacing parts.

Theory of Operation

Under normal operation, the body control electronics supply power to the right parking lamp/DRL circuit and regulate it based on the selected lighting mode. The module also runs bulb diagnostics. It does this by monitoring the output driver’s electrical behavior during and after the command.

B19B2 sets when the module commands the right parking lamp/DRL and sees an “open” signature, or when it sees battery positive on the lamp feed in an unexpected state. An open usually comes from a broken wire, a loose terminal, corrosion, or an internal open in the lamp unit. A short to positive often comes from harness chafing into a B+ source, water intrusion in a connector, or a backfeed from an incorrectly wired lamp assembly.

Symptoms

You will usually notice a right-side lighting problem first, then a stored body DTC.

• Inoperative lamp Right parking lamp or right DRL does not illuminate.
• Stuck on Right parking lamp/DRL stays on with the switch off or after shutdown.
• Flicker Right DRL/parking lamp flickers, especially over bumps or during rain.
• Bulb warning Cluster displays a lamp failure warning or exterior light message.
• Uneven brightness Right side looks dimmer or brighter than the left.
• Intermittent operation Lamp works sometimes, then fails again after driving.
• Stored code B19B2 returns quickly after clearing when the lights turn on.

Common Causes

• Open circuit in the right parking lamp/DRL feed: A broken wire or separated terminal stops current flow, so the control module sees no load and flags an open circuit.
• Short to positive in the lamp output circuit: Contact with a battery-fed wire or an internal short keeps the circuit powered when it should not, so the module detects an implausible high output state.
• Connector corrosion at the right headlamp assembly: Corrosion adds resistance and intermittently opens the circuit, which mimics an open load during lamp checks.
• Terminal push-out or poor pin fit at the lamp or module connector: A loose terminal makes contact only sometimes, so the module sees the circuit switch between normal and open.
• Water intrusion in the headlamp or harness: Moisture bridges terminals and creates leakage paths that can pull the circuit toward battery positive.
• Incorrect bulb type or wrong LED retrofit: The circuit load changes and can confuse Mercedes-Benz lamp diagnostics, which can set a fault even when the lamp lights.
• Internal fault in the right lamp/DRL electronics (if equipped): A failed driver or LED board can open the load path or backfeed voltage into the control line.
• Chafed harness at common Sprinter 907 routing points: Harness rub-through near the headlamp area can open the conductor or short it to a nearby power feed.
• Power distribution issue feeding the exterior lighting circuit: A weak fuse contact or faulty power feed can drop voltage under load and look like an open circuit to the module.

Diagnosis Steps

Use a scan tool that can access Mercedes-Benz body and lighting functions, plus live data and actuator tests. Have a DMM and a test light or headlamp-style load tool. Use back-probes, terminal tension tools, and basic harness repair supplies. You will also need wiring diagrams for the exact Sprinter 907 configuration.

1. Confirm B19B2 in the vehicle scan. Record whether the code shows as pending or stored. Save freeze frame data, especially battery voltage, ignition state, and exterior lighting switch state when the DTC set.
2. Do a fast visual inspection before any meter work. Check the right parking lamp/DRL lens, bulb, and socket condition. Inspect the harness from the headlamp area to the first connector for rub-through, crushed sections, or previous repair work.
3. Check fuses and power distribution for the exterior lighting system first. Do not jump to module pin testing yet. Verify the correct fuses for right-side parking lamp/DRL and any lamp supply circuits, and confirm the fuse blades and terminals fit tightly.
4. Prove power integrity under load at the fuse output. Turn the parking lamps or DRL function on. Use a test light or load tool to confirm the fuse output carries current without dropping out.
5. Verify control module power and ground integrity under load. Command the parking lamp/DRL on with the switch or scan tool. Perform voltage-drop tests on the module grounds while the circuit operates, and keep ground drop under 0.1 V with the load active.
6. Inspect the right headlamp connector and any inline connectors in the circuit path. Look for water tracks, green corrosion, overheated terminals, or backed-out pins. Confirm terminal tension by gently drag-testing the male pins with the connector unplugged.
7. Use live data to compare requested state versus actual feedback. Many Mercedes-Benz body modules report lamp request and lamp fault status. If the module shows “ON” request but “open load” status, focus on opens and high resistance. If it shows “OFF” request but “voltage present,” focus on a short to positive or backfeed.
8. Run an actuator test for the right parking lamp/DRL output, if available. Watch the lamp and monitor live data during the test. If the lamp does not respond, continue with circuit testing at the lamp side before condemning a module.
9. Test for an open circuit on the lamp feed and return path using loaded methods. With the circuit commanded ON, measure voltage at the lamp connector. If voltage appears but the lamp stays out, load-test the ground side with a test light to battery positive to catch a weak return.
10. Test for a short to positive with the circuit commanded OFF. Disconnect the right lamp connector and recheck the control wire at the harness side. If the wire still shows battery voltage when it should not, isolate sections of the harness and connectors until the backfeed source disappears.
11. Use a scan tool snapshot during a road test if the concern is intermittent. Freeze frame shows conditions when the DTC set. A snapshot captures live voltage status, lamp request, and fault flags at the moment the lamp flickers or the warning appears.
12. After repairs, clear codes and rerun the actuator test. Cycle the ignition and operate parking lamps and DRL modes. Confirm the code does not return immediately at key-on, which usually indicates a hard fault on a continuously monitored circuit.

Professional tip: Treat “short to positive or open circuit” as two different failure paths and prove which one you. An open shows normal control commands but no current flow. A short to positive shows voltage present even when the module commands the output off. Disconnecting the lamp and isolating harness sections quickly separates a harness short from an internal lamp backfeed.

Possible Fixes

• Repair an open or high-resistance section in the right parking lamp/DRL circuit: Restore conductor integrity and verify operation under load after the repair.
• Clean and restore connector terminal contact: Remove corrosion, correct terminal tension issues, and address water intrusion sources before reassembly.
• Repair a short-to-positive in the harness: Locate chafe points, reroute or protect the harness, and confirm the circuit stays low when commanded off.
• Correct bulb or lamp assembly configuration: Install the correct bulb type or correct lamp electronics so the Mercedes-Benz lamp monitoring sees an expected load.
• Replace the right lamp/DRL unit only after circuit proof: Replace the assembly if it backfeeds voltage or shows an internal open with known-good power and ground.
• Restore power distribution integrity: Repair loose fuse terminals or related supply issues that drop voltage under load and mimic an open circuit.

Can I Still Drive With B19B2?

You can usually drive a Mercedes-Benz Sprinter 907 with B19B2, but you should treat it as a road-safety and legal-compliance issue. This code points to a right parking lamp/DRL circuit fault described as short to positive or open circuit. That can leave the right side light inoperative, dim, or stuck on. Reduced conspicuity matters most at dusk, dawn, rain, fog, and in traffic. If the lamp stays on, it can drain the battery during long parking periods. If the vehicle reports multiple exterior light faults, avoid night driving until you confirm proper lighting operation.

How Serious Is This Code?

B19B2 ranges from an inconvenience to a real safety concern. It stays mostly inconvenient when the right parking lamp/DRL still works and the fault sets intermittently, often from a poor connection. It becomes more serious when the right-side lamp stays off, since other drivers lose a key visual cue. A short to positive can also backfeed other lighting circuits on some Mercedes-Benz platforms. That can trigger additional body DTCs and strange lamp behavior. This code does not affect engine drivability, but it can affect roadworthiness inspections and nighttime safety.

Common Misdiagnoses

Technicians often replace the right DRL/parking bulb or LED module first and stop there. That misses the two failure types in the description: open circuit and short to positive. Another common error involves testing voltage with the lamp disconnected and calling the circuit good. The circuit can fail only under load, so you must check voltage drop and connector pin fit with the lamp powered. Many shops also ignore water intrusion at the lamp housing connector and focus on the front SAM or body controller too early. Confirm the harness, grounds, and connector condition before suspecting a module output stage.

Most Likely Fix

The most frequently confirmed repair directions for B19B2 involve correcting a wiring or connection fault at the right parking lamp/DRL. Start with connector corrosion, pushed-out terminals, damaged insulation, or harness chafing that can create an intermittent open. Next, hunt for a short to positive from rubbed-through wiring contacting a power feed, or from moisture bridging terminals inside the connector. Only after you verify proper power, ground integrity, and commanded output behavior should you consider a lamp assembly fault or a failed control module driver. After repair, recheck operation under the same conditions that set the code, since enable criteria vary by Mercedes-Benz platform.

Repair Costs

Repair cost depends on whether the confirmed root cause is a sensor, wiring, connector issue, or control module problem. Verify the fault electrically before replacing parts.

Last updated: March 30, 2026