How to Connect Electronic Stability Control (ESC) to your caravan?
David received a question about connecting the ESC to the caravan batteries in the Jayco Crosstrak.
Question: Complete caravan novice here. I have a Jayco Crosstrak (and still waiting for delivery of a new Prado) and have installed WiTi Antitheft and Wireless brake controller. I am planning to use their wireless towing interface.
Is there any reason why I cannot connect the ESC to the caravan batteries? (from Christopher)
Answer (David Bayliss): Thanks for your question and one which yet we have not covered. The WITI product is a relative newcomer onto the market and as such I have not seen a lot of commentary in regard to its interoperability with trailer brakes. However, after digesting its product info and our intimate knowledge of sway systems such as the ESC and BMPRO SwayControl, I am happy to share the following.
The ESC system has been designed to take power from the towing vehicle and as such it recommended wiring appropriately through a 12pin plug or via a separate two pin Anderson connection. It recommends constant power supplied from the tow vehicle, whereas in comparison the BMPRO SwayControl is designed to maximise the opportunity to utilise the caravan house battery. There are benefits and pitfalls of both.
The ESC system from AL-KO is suitable where there is no battery in the caravan and thus can use the power from the towing vehicle. The downfall, in my experience with this system, is that you need to ensure that your connections from the towing vehicle are well maintained and in tip top working condition, otherwise you can experience the ESC cutting in and out when it is required without the driver have any knowledge of this actually happening.
The BMPRO SwayControl, however, enables you to utilise the house battery in your caravan and is powered directly from this battery. So, you will need to ensure that there a battery onboard and that it is maintained and charged to such a level that can provide the adequate power requirements.
Therefore, I would strongly recommend that you keep the ESC wiring powered from the tow vehicle as per the manufacturer’s recommendations. To ensure that these safety systems work effectively it is imperative that the wiring for the ESC is kept as a dedicated system. From a power management and earthing perspective, it would also be wise to ensure that the WITI system is kept dedicated to its purposes and the ESC is left independent to function effectively. It is recommended that only authorised installers operate on this ESC system to ensure its integrity.
Unlike the SwayControl, the ESC system does not have an off-road mode and therefore when rounding kerbs/roundabouts or heading offroad if not separated from its power source such as the 12V Anderson connection from the towing vehicle it is likely to activate the brakes on the caravan unnecessarily. Therefore, if the ESC was connected directly to the caravan batteries it could cause unnecessary braking in rough terrain due to its permanent power source. In addition, if a constant power source is supplied to the ESC, it is likely to drain the house battery whereas when if it is power only from the towed vehicle, when the ignition is turned off then so does the ESC thus preventing battery drain.
Therefore overall, we would strongly suggest to only install safety systems such as the ESC or SwayControl exactly as per the manufacturer’s recommendations to ensure that it meets your expectations especially in the case of extreme emergency.