MERCEDES CLA Towbar Wiring Kits

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

Mercedes CLA Saloon Trailer Electrics Compatibility

For the Mercedes CLA Saloon, dedicated wiring kits are available for vehicles from 2013 onwards, covering both the first generation (up to 03/2019) and the later models from 04/2019. These kits are designed to interface with the CLA's CAN bus network and body control modules for reliable trailer lighting control.

Both 7-pin and 13-pin socket configurations are supported, depending on the selected kit and model year. This allows correct operation of tail lights, brake lights, indicators and rear fog lights on trailers, caravans or rear-mounted carriers equipped with lighting.

Some CLA variants are equipped with an OE towing or trailer pre-installation module (PR-code 1D7). For these vehicles, specific kits are available that integrate with the existing OE module rather than bypassing it, ensuring that the vehicle continues to monitor and manage trailer-related functions as intended.

On modern Mercedes electronics, coding or activation via diagnostic equipment may be required after installation so that trailer monitoring, bulb failure detection and stability systems recognise the connected towbar wiring. Always follow the installation manual for coding steps appropriate to the CLA production period in question.

Vehicle Technology Compatibility For Mercedes CLA Saloon

• Parking sensors: Dedicated wiring can support deactivation or reduction of rear parking sensor alerts when a trailer is connected, helping to avoid constant acoustic warnings.
• Trailer Stability Program (TSP): Correct integration with the CAN bus allows the vehicle to detect a trailer and activate Trailer Stability or related ESP algorithms where fitted.
• Rear fog light deactivation: When wired correctly, the CLA's rear fog lamp can be deactivated automatically with a trailer connected so that only the trailer fog lamp operates, improving visibility and reducing glare.
• Check control and bulb monitoring: Dedicated modules are designed to work with Mercedes bulb failure monitoring, reducing false warnings and ensuring trailer light failures are correctly detected where the vehicle supports this.
• CLA model year coverage: Wiring solutions are available for CLA Saloon models up to 03/2019 and from 04/2019 onwards; always choose a kit that matches the vehicle build date and electrical architecture.
• OE module (PR-code 1D7): Some later CLA models with OE trailer preparation require specific wiring kits that connect to the factory module; using the correct variant helps maintain all factory towing functions.

Towbar Wiring Kit Installation Notes For Mercedes CLA Saloon

• Use a CLA-specific wiring kit that matches the body type (Saloon) and production period (for example, pre-03/2019 or from 04/2019 onwards) to ensure correct connector locations and harness lengths.
• For Saloon models from 04/2019 with OE module preparation (PR-code 1D7), select the corresponding kit designed to work with the existing module rather than generic bypass solutions.
• Some 13-pin kits specify additional extension kits for power supply to caravan interior loads or battery charging; check the documentation for required add-on harnesses before starting installation.
• Plan for an estimated installation time of 45–60 minutes on later CLA models and 60+ minutes on earlier models, depending on trim removal, cable routing and any required coding.
• Maintain an OEM-style fit by routing the harness along factory paths, using existing grommets where possible and securing cables to avoid chafing or mechanical stress.
• Apply corrosion protection to any bodywork penetrations and ensure grommets and seals are fully reseated after passing the wiring through the rear panel or spare wheel well.
• After installation, function-test all trailer lights and verify that any dash warnings, parking aids and stability systems behave as described in the installation manual.

Related Mercedes Models With Towbar Wiring Kits

If you operate multiple Mercedes vehicles alongside your CLA Saloon, dedicated wiring solutions are also available for other models in the range. These systems follow similar integration principles but are tailored to each platform's electronics and body style.

• Mercedes A-Class towbar wiring kits
• Mercedes B-Class towbar wiring kits
• Mercedes C-Class towbar wiring kits
• Mercedes GLC towbar wiring kits
• Mercedes GLE towbar wiring kits

Frequently Asked Questions About Mercedes CLA Towbar Wiring Kits

Do Mercedes CLA Saloon models from 2013 to 2019 use the same towbar wiring as later models from 2019 onwards?
No. Early CLA Saloon models up to 03/2019 use different wiring solutions to later vehicles from 04/2019 onwards, so the wiring kit must match the vehicle production period and electrical architecture.

Can a 7-pin towbar wiring kit be used on a Mercedes CLA Saloon with a caravan that has a 13-pin plug?
Yes, but you will need an external 7-pin to 13-pin adapter to connect a 13-pin caravan to a 7-pin CLA socket; for full caravan functionality, including permanent and switched feeds, a dedicated 13-pin wiring kit is recommended.

How does a dedicated wiring kit affect the parking sensors on a Mercedes CLA Saloon?
When correctly installed and coded, a dedicated wiring kit can signal the control unit that a trailer is connected, enabling automatic deactivation or reduction of rear parking sensor alerts to prevent continuous beeping when towing.

Are special wiring kits required for Mercedes CLA models with the OE trailer preparation module (PR-code 1D7)?
Yes. CLA models with OE trailer preparation use a factory module, so you must choose a wiring kit designed to integrate with that module and its connectors instead of a standard standalone towbar wiring harness.

Do I need diagnostic coding after fitting a towbar wiring kit to my Mercedes CLA Saloon?
In many CLA variants, diagnostic coding is required so that the vehicle recognises the trailer module, correctly manages bulb failure monitoring, adjusts stability functions and modifies parking sensor behaviour when a trailer is connected.