MazicBay Diagnostics
MAZICBAYDiagnostics
FTC Reader Disclosure: When you purchase or register through links on our site, we may earn an affiliate commission at no extra cost to you. Read our Editorial & Advertising Policy.

P0155 on Mercedes-Benz GLE

O2 Sensor Heater Circuit Malfunction (Bank 2 Sensor 1)

Factory diagnostic protocol and troubleshooting wire for fault code P0155 specifically for the Mercedes-Benz GLE (2020–2026, 2.0L Turbo / 3.0L Turbo I6 (GLE 450 375HP) / 4.0L V8 GLE 580).

Verified OEM Telemetry & Field Repair Tree
Mercedes-Benz GLE2020–2026
Mercedes-Benz GLE
SUV2.0L Turbo / 3.0L Turbo I6 (GLE 450 375HP) / 4.0L V8 GLE 580
Reliability
Sensor Voltage Ref
0.1V – 5.0V Ref
GLE 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
$120 - $350 (DIY: $45 - $120)
Parts & Labor DIY
Check P0155 On Another Mercedes-Benz Model:
Diagnose P0155 on Specific GLE Model Year:

1. Symptoms of P0155 on Mercedes-Benz GLE

When the Engine Control Module (ECM/PCM) on your Mercedes-Benz GLE (2.0L Turbo / 3.0L Turbo I6 (GLE 450 375HP) / 4.0L V8 GLE 580) logs fault code P0155, drivers commonly observe:

Check Engine Light on immediately after cold start on Mercedes-Benz GLE (2.0L Turbo / 3.0L Turbo I6 (GLE 450 375HP) / 4.0L V8 GLE 580)
Slightly increased cold-start emissions on Mercedes-Benz GLE (2.0L Turbo / 3.0L Turbo I6 (GLE 450 375HP) / 4.0L V8 GLE 580)
No major driving performance issues once engine reaches full operating temperature on Mercedes-Benz GLE (2.0L Turbo / 3.0L Turbo I6 (GLE 450 375HP) / 4.0L V8 GLE 580)
Mercedes-Benz GLE OBD-II Port Location
The 16-pin diagnostic connector is located Driver footwell directly above parking brake pedal. Plug in your scan tool to verify freeze-frame sensor values.

2. Most Likely Causes on Mercedes-Benz GLE

Historical warranty claims and technical repair bulletins for Mercedes-Benz GLE point to the following failure distribution:

55%
Burnt-out heating element inside the Bank 2 Sensor 1 O2 sensor (Mercedes-Benz OEM Part)
25%
Blown O2 heater fuse in under-hood fuse block (Mercedes-Benz OEM Part)
12%
Corroded or broken heater power/ground wiring (Mercedes-Benz OEM Part)
8%
Faulty heater driver circuit in the PCM (Mercedes-Benz OEM Part)
* Source: Synthesized from NHTSA ODI field repair telemetry and verified OEM Technical Service Bulletin (TSB) repair tree frequency percentiles for Mercedes-Benz GLE.

3. Step-by-Step DIY Repair Guide for Mercedes-Benz GLE

01
Check O2 Heater Fuse

Inspect the O2 HTR fuse in the engine fuse box with a test light or multimeter. on the Mercedes-Benz GLE equipped with 2.0L Turbo / 3.0L Turbo I6 (GLE 450 375HP) / 4.0L V8 GLE 580.

Required Tool: Fuse Puller, Test Light
02
Test Heater Resistance on Bank 2 Sensor 1

Unplug the sensor connector and measure resistance between the two heater pins. An open circuit (infinite ohms / OL) confirms a dead internal heater. on the Mercedes-Benz GLE equipped with 2.0L Turbo / 3.0L Turbo I6 (GLE 450 375HP) / 4.0L V8 GLE 580.

Required Tool: Digital Multimeter
03
Replace Bank 2 Upstream O2 Sensor

Remove faulty sensor and install a new OEM oxygen sensor with built-in heater. on the Mercedes-Benz GLE equipped with 2.0L Turbo / 3.0L Turbo I6 (GLE 450 375HP) / 4.0L V8 GLE 580.

Required Tool: 22mm O2 Sensor Socket, Ratchet
04
Clear Codes and Perform Cold Start Verification

Clear DTCs and allow engine to cool down, then restart to confirm P0155 does not return. on the Mercedes-Benz GLE equipped with 2.0L Turbo / 3.0L Turbo I6 (GLE 450 375HP) / 4.0L V8 GLE 580.

Required Tool: OBD-II Scanner
Recommended Parts & Testing Tools

Equipment for Diagnosing Mercedes-Benz GLE (P0155)

Prime Fast Delivery & Verified Fitment
Direct-Fit Replacement Part

Mercedes-Benz GLE OEM Replacement Sensor

4.7 / 5.0 (Verified Fit)

Direct-fit replacement assembly engineered to OEM tolerances for Mercedes-Benz GLE.

$45 – $95 Prime
Check Fitment on Amazon
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 Mercedes-Benz GLEVerified direct-fit pricing from Denso, Bosch, Motorcraft, and ACDelco on Amazon.
Find Parts on Amazon
* As an Amazon Associate, MazicBay earns from qualifying purchases. Prices & availability subject to change.

Other Common Fault Codes on Mercedes-Benz GLE

Frequently diagnosed powertrain, emissions, and sensor trouble codes logged on the Mercedes-Benz GLE:

4. Mercedes-Benz GLE P0155 FAQs

What causes code P0155 to trigger on a Mercedes-Benz GLE?

On the Mercedes-Benz GLE (2.0L Turbo / 3.0L Turbo I6 (GLE 450 375HP) / 4.0L V8 GLE 580), P0155 is most frequently caused by Burnt-out heating element inside the Bank 2 Sensor 1 O2 sensor or Blown O2 heater fuse in under-hood fuse block.

Where is the OBD-II port located on my Mercedes-Benz GLE?

On the Mercedes-Benz GLE, the 16-pin DLC diagnostic connector is located Driver footwell directly above parking brake pedal. Plug in any standard OBD-II scanner with the ignition in the ON position to read freeze-frame parameters.

Can I safely drive my Mercedes-Benz GLE with code P0155?

Yes. The sensor will take longer to warm up, causing brief open-loop fuel delay on cold starts. Given that P0155 carries a Medium severity rating, we advise avoiding heavy towing or aggressive throttle inputs until sensor readings are verified.