MERCEDES GLA Towbar Wiring Kits

The Mercedes GLA saloon can be equipped for towing caravans, trailers or rear-mounted bike carriers with vehicle-specific towbar wiring kits. These kits interface with the factory electronics to ensure correct trailer lighting functions and system diagnostics.

We can't find products matching the selection.

For other MERCEDES models, see the Mercedes towbar wiring kits overview.

MERCEDES GLA Trailer Electrics Compatibility

For the MERCEDES GLA, ECS offers dedicated towbar wiring kits matched to GLA production periods from 03/2014 onwards. Kits are designed for SUV-type GLA variants and support standard trailer lighting functions with either 7-pin or 13-pin sockets, depending on the selected kit.

On earlier GLA models (03/2014–02/2020), dedicated kits are available with 7-pin or 13-pin connectors. Later GLA models from 03/2020 onwards use vehicle-specific 7-pin/PA or 13-pin/PA solutions, with variants for vehicles equipped with an OE trailer module (PR-code: 1D7). This ensures correct communication with factory control units.

The wiring kits are engineered to work with the GLA's multiplexed CAN-bus system, ensuring correct operation of indicators, brake lights, side lights and rear fog lights on the trailer or accessory. Indicator monitoring is integrated so that trailer light failures can be detected by the vehicle where supported.

Some GLA versions may require coding or activation via diagnostic equipment after installation so that the vehicle recognises the trailer module and enables trailer-related functions. Always follow the vehicle-specific installation manual and, where required, perform coding with suitable diagnostic tools.

Vehicle Technology Compatibility

Parking sensors: Dedicated wiring supports correct interaction with rear parking sensors; on many GLA versions, trailer detection allows the parking aid to be reduced or deactivated when towing.
Trailer Stability Program (TSP): When the vehicle supports TSP, correct trailer recognition via the towbar wiring is important so that stability control can adapt to trailer use.
Rear fog light deactivation: Vehicle-specific electrics allow automatic deactivation of the vehicle rear fog lamp when a trailer is connected, where this function is supported by the GLA electronics.
Check control integration: The wiring kits are designed to cooperate with the GLA bulb failure and check control systems so that trailer lighting faults can be monitored according to vehicle capability.
OE trailer module vehicles (PR-code 1D7): For GLA models equipped with an original equipment trailer module, specific 7-pin/PA and 13-pin/PA kits are available that integrate with the existing OE module instead of duplicating functions.
Energy management systems: On newer GLA generations, vehicle-specific wiring protects sensitive electronic systems and helps maintain correct load management on the electrical network.

Towbar Wiring Kit Installation Notes For This Model

Use vehicle-specific GLA wiring kits matched to the correct production period (03/2014–02/2020 or from 03/2020 onwards) to ensure compatibility with the SUV body and electronics.
On some 13-pin kits, additional extension kits (for example for permanent power or charging lines) are required; always consult the specific installation instructions before starting work.
For GLA models with an OE trailer module (PR-code 1D7), select the corresponding kit variant designed to interface with the factory control unit.
Observe the indicated installation times (typically 45–60 minutes or 60+ minutes) as a guideline only; actual times can vary with workshop equipment and vehicle specification.
Maintain an OEM-style fit by routing cables along existing harness paths, using original grommets where possible, and protecting all passes through metal panels against chafing and corrosion.
Ensure all connections are secure, correctly fused where applicable, and that any required coding or adaptation is completed so the GLA recognises trailer operation.
After installation, test all trailer lighting functions and check that vehicle systems such as parking sensors and warning indicators respond correctly with a test board or trailer connected.
Check the vehicle handbook or VIN plate for exact towing limits before using the towbar with a caravan, trailer or accessory.

Related MERCEDES Models With Towbar Wiring Kits

Drivers considering a MERCEDES GLA towbar wiring kit may also need trailer electrics for other models in the MERCEDES range. ECS supplies dedicated solutions for various saloon, estate and SUV vehicles within the brand.

Frequently Asked Questions About MERCEDES GLA Towbar Wiring Kits

Does a MERCEDES GLA with parking sensors need a specific towbar wiring kit?

Yes. A vehicle-specific GLA wiring kit helps the parking sensors recognise when a trailer is connected so that the rear acoustic warnings can be reduced or suppressed, depending on the vehicle configuration.

Which socket type do I need for my MERCEDES GLA towbar electrics?

For basic trailer lighting and many bike carriers, a 7-pin socket is sufficient. For caravans or accessories requiring continuous power or fridge supply, choose a 13-pin solution and, where specified, the matching extension kit.

How do I know which GLA production period my towbar wiring kit must cover?

Check the vehicle registration document or VIN to confirm whether your GLA is from the 03/2014–02/2020 generation or from 03/2020 onwards, then select a wiring kit specified for that period.

What is important for MERCEDES GLA models with an OE trailer module (PR-code 1D7)?

GLA models with PR-code 1D7 require wiring kits designed to integrate with the existing OE trailer control module. Using the correct kit variant ensures proper communication with the factory electronics.

Is coding required after fitting a towbar wiring kit to a MERCEDES GLA?

Many GLA versions require coding or activation via diagnostic equipment so that the vehicle enables trailer functions such as bulb monitoring and Trailer Stability Program. Always follow the specific fitting instructions.

Next Steps For MERCEDES GLA Towbar Electrics

Use the wiring kits listed on this page to select a solution that matches your MERCEDES GLA production year, socket type and equipment level. If you operate multiple MERCEDES vehicles, you can also view other dedicated applications in the Mercedes towbar wiring kits range.

FIND YOUR TOWBAR WIRING KIT