Glow Plug Control Relay A6429001402 – Diesel Relay for Mercedes

The glow plug control relay (OEM A6429001402) is a critical engine electrical component designed to manage the activation of glow plugs in diesel engines, particularly in Mercedes-Benz applications. This relay regulates the electric current supplied to the glow plugs during engine start-up, ensuring proper pre-heating of each cylinder for efficient cold starts and reduced emissions. When this control relay fails, it can lead to hard starting, extended crank times, and increased white smoke during start-up. This replacement part is designed to match the original specification for reliable performance and direct fitment.

OEM Number: K68013182AD, K68013182AC, K68013182AB, K68013182AA, A6421532079, A6421530379, A6421531979, 6429001402

GLOW PLUG CONTROL UNIT RELAY
EASY INSTALL - DIRECT REPLACEMENT 
2 PLUGS - 1 AND 12 PINS

Voltage: 12V 

Quantity : 1

Our SKU: TMA6429002800_94

All our Glow Plug Control Relay A6429001402 are OEM quality and reliable after market car parts. This Glow Plug Control Relay A6429001402 is specifically compatible with Chrysler: 300C, Jeep: Grand Cherokee, Mercedes-Benz: C-Class, CLK, CLS, E-Class, G-Class, GL-Class, GLK-Class, M-Class, R-Class, S-Class, Sprinter 3-T, Sprinter 3.5-T, Sprinter 4-T, Sprinter 4.6-T, Sprinter 5-T, Viano, Vito, Vito / Mixto, .

Please use our make-model-year tool to check this part's compatibility with your vehicle. However, please note that our tool is for reference only and we recommend that you check the part number on your old unit prior to purchasing.

If you are still not sure about the compatibility of this part to your vehicle, please supply us with the VIN number or Reg number in our live chat or contact form! You can also find details on our purchasing & shipping guide here.

Key Benefits

Accurate Glow Plug Current Control
The control relay regulates electrical current to the glow plugs based on signals from the engine control unit, ensuring each glow plug receives the correct power for efficient heating and reliable cold-start performance. 

Direct Replacement for A6429001402
Designed to match original equipment part number A6429001402, this relay installs in place of the factory part without modification, helping maintain proper engine start performance.

Improves Cold Start Performance
A functioning glow plug control relay helps ensure quicker, smoother engine starts in diesel vehicles, particularly in cold weather conditions where pre-heating is essential.

Supports Emissions Control
By properly managing glow plug activation timing, the relay contributes to more complete combustion at start-up, which can help reduce unburned fuel emissions and white exhaust smoke.

Enhances Reliability and Engine Health
Replacing a worn or faulty relay can prevent starter strain and reduce the risk of glow plug damage due to improper current regulation, helping maintain long-term engine reliability.

Frequently Asked Questions (FAQs)

Q: What does a glow plug control relay do?
A: The glow plug control relay regulates the electric current supplied to the glow plugs, based on data from the engine control module (ECU), to ensure proper pre-heating of the combustion chamber before engine start-up. This controlled activation improves cold starting and reduces emissions.

Q: What are symptoms of a failing glow plug control relay?
A: Common symptoms include difficulty starting the engine in cold conditions, extended cranking time, persistent glow plug warning lights, and white smoke during start-up.

Q: Can this relay be fitted to my vehicle easily?
A: Yes, this glow plug control relay is designed to be a direct replacement for the original OEM unit with reference A6429001402 and installs without modification when matched to the correct vehicle application.

Q: Which Mercedes engines commonly use this relay?
A: This relay is commonly used with diesel engines such as the Mercedes OM642 V6 and other compatible CDI diesel models where part number A6429001402 is specified. Always confirm part compatibility with your VIN or existing part number before ordering.

Q: Will replacing the relay fix starting problems?
A: If the cause of hard starts or glow plug faults is traced to a faulty control relay, replacing it typically resolves those issues. However, diagnostic testing is recommended to rule out other potential causes such as faulty glow plugs or wiring.