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P0230 on Mercedes-Benz GLS

Fuel Pump Primary Circuit Malfunction

Factory diagnostic protocol and troubleshooting wire for fault code P0230 specifically for the Mercedes-Benz GLS (2020–2026, 3.0L Turbo I6 (GLS 450) / 4.0L Bi-Turbo V8 (GLS 580 / Maybach)).

Verified OEM Telemetry & Field Repair Tree
Mercedes-Benz GLS2020–2026
Mercedes-Benz GLS
SUV3.0L Turbo I6 (GLS 450) / 4.0L Bi-Turbo V8 (GLS 580 / Maybach)
Reliability
Sensor Voltage Ref
0.1V – 5.0V Ref
GLS SAE Mode $01
ECU Network Bus
500 kbps CAN-FD
ISO 15765-4 Compliant
Drivability Status
Not Recommended
Critical urgency level
Est. Repair Cost
$100 - $650 (DIY: $20 - $180)
Parts & Labor DIY
Check P0230 On Another Mercedes-Benz Model:
Diagnose P0230 on Specific GLS Model Year:

1. Symptoms of P0230 on Mercedes-Benz GLS

When the Engine Control Module (ECM/PCM) on your Mercedes-Benz GLS (3.0L Turbo I6 (GLS 450) / 4.0L Bi-Turbo V8 (GLS 580 / Maybach)) logs fault code P0230, drivers commonly observe:

Engine cranks but will not start (No fuel delivery) on Mercedes-Benz GLS (3.0L Turbo I6 (GLS 450) / 4.0L Bi-Turbo V8 (GLS 580 / Maybach))
Engine suddenly dies while driving and won't restart on Mercedes-Benz GLS (3.0L Turbo I6 (GLS 450) / 4.0L Bi-Turbo V8 (GLS 580 / Maybach))
Check Engine Light illuminated on Mercedes-Benz GLS (3.0L Turbo I6 (GLS 450) / 4.0L Bi-Turbo V8 (GLS 580 / Maybach))
No fuel pump humming sound from gas tank when key is turned ON on Mercedes-Benz GLS (3.0L Turbo I6 (GLS 450) / 4.0L Bi-Turbo V8 (GLS 580 / Maybach))
Mercedes-Benz GLS OBD-II Port Location
The 16-pin diagnostic connector is located Driver lower knee bolster trim panel. Plug in your scan tool to verify freeze-frame sensor values.

2. Most Likely Causes on Mercedes-Benz GLS

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

55%
Blown fuel pump fuse or burnt fuel pump relay (Mercedes-Benz OEM Part)
25%
Open or shorted control circuit wiring between PCM and fuel pump relay (Mercedes-Benz OEM Part)
12%
Faulty Fuel Pump Driver Module (FPDM) (Mercedes-Benz OEM Part)
8%
Corroded ground wire near fuel tank (Mercedes-Benz OEM Part)
8%
Failing in-tank electric fuel pump (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 GLS.

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

01
Check Fuel Pump Fuse & Swap Relay

Inspect the Fuel Pump fuse in under-hood fuse box. Swap the fuel pump relay with an identical non-critical relay (like the horn relay). on the Mercedes-Benz GLS equipped with 3.0L Turbo I6 (GLS 450) / 4.0L Bi-Turbo V8 (GLS 580 / Maybach).

Required Tool: Fuse Puller, Test Light
02
Listen for Fuel Pump Prime

Have an assistant turn key to ON while listening at the open fuel filler neck. A healthy pump hums for 2–3 seconds. on the Mercedes-Benz GLS equipped with 3.0L Turbo I6 (GLS 450) / 4.0L Bi-Turbo V8 (GLS 580 / Maybach).

Required Tool: Helper
03
Test Relay Socket Terminals

Check for 12V battery power on pin 30 and 86, and check for PCM ground command on pin 85 when key is turned on. on the Mercedes-Benz GLS equipped with 3.0L Turbo I6 (GLS 450) / 4.0L Bi-Turbo V8 (GLS 580 / Maybach).

Required Tool: Digital Multimeter
04
Inspect Fuel Pump Driver Module (FPDM)

On vehicles with an electronic FPDM (such as Ford F-150s mounted on rear axle), check for corrosion or cracked aluminum housing. on the Mercedes-Benz GLS equipped with 3.0L Turbo I6 (GLS 450) / 4.0L Bi-Turbo V8 (GLS 580 / Maybach).

Required Tool: Flashlight, 10mm Socket
05
Replace Fuel Pump Assembly if Necessary

If power and ground reach the pump connector but pump does not spin, drop tank or access fuel pump hatch to replace pump assembly. on the Mercedes-Benz GLS equipped with 3.0L Turbo I6 (GLS 450) / 4.0L Bi-Turbo V8 (GLS 580 / Maybach).

Required Tool: Lock Ring Tool, Jack Stands, Fuel Line Disconnect
Recommended Parts & Testing Tools

Equipment for Diagnosing Mercedes-Benz GLS (P0230)

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Mercedes-Benz GLS OEM Replacement Sensor

4.7 / 5.0 (Verified Fit)

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

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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.

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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.

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Other Common Fault Codes on Mercedes-Benz GLS

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

4. Mercedes-Benz GLS P0230 FAQs

What causes code P0230 to trigger on a Mercedes-Benz GLS?

On the Mercedes-Benz GLS (3.0L Turbo I6 (GLS 450) / 4.0L Bi-Turbo V8 (GLS 580 / Maybach)), P0230 is most frequently caused by Blown fuel pump fuse or burnt fuel pump relay or Open or shorted control circuit wiring between PCM and fuel pump relay.

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

On the Mercedes-Benz GLS, the 16-pin DLC diagnostic connector is located Driver lower knee bolster trim 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 Mercedes-Benz GLS with code P0230?

No. The engine will crank but not start or will suddenly stall while driving when the fuel pump cuts out. Given that P0230 carries a Critical severity rating, we advise avoiding heavy towing or aggressive throttle inputs until sensor readings are verified.