I would like to fit a second battery to my Auto-Trail motorhome

I would like to fit a second battery to my Auto-Trail motorhome

Fitting a second leisure battery to an Auto-Trail vehicle is usually straight forward.  All current and most older models come equipped with a dedicated connector to allow an additional battery harness to be plugged in, making the whole process a plug and play affair. 

When fitting a second battery it is always best to fit the same manufacturer, type and capacity as the original.  However we appreciate that this isn’t always possible, but please try to keep to the same capacity and don’t mix battery types (i.e. don’t mix ‘wet’ and AGM).

Here is an image of the battery harness:

This is the new type as fitted to Auto-Trail vehicles from 2011 onwards.  If you have an older van you can either order the older type (again available from our web shop), but the newer version above will fit your vehicle as the battery connector is the same.

The harness should be connected to your new leisure battery, ensuring both terminals are good and tight and that the terminal covers are in place, and the battery fitted and secured in the battery box / compartment (depending upon year/model) ensuring the harness isn’t trapped.

You can now plug your new battery into the vehicle harness, noting that the additional battery connector is fitted with a protective cap which needs to be removed, as shown below.

If you have an EC328 or EC700 system you are now ready to charge and use your additional leisure battery.

If you have an EC500 fitted with the EC480 colour LCD control panel, you should set the battery capacity to match your new configuration (i.e., if you had a single 100Ah battery and fitted a second 100Ah battery you should change the battery capacity to 200Ah in the advanced settings and calibrate the current sensor.

To access the advanced settings, on the home screen (the one with the company / brand logo), press and hold the up and down arrows together. Continue holding these buttons until the screen changes.  Scroll down to ‘Battery Size’ then use the select button to increase to the required battery size, then scroll up to ‘Exit Advanced’ and use the select button to go back to normal operation. 

Note, after this the Ah reading will have reduced; this will take several cycles of charge / discharge to get into sync with the actual battery capacity – this is quite normal and nothing to be concerned about.  

To calibrate the current sensor, turn off the charger and the control panel power button, then scroll to the active battery screen, press and hold the select button until the 'calibrating please wait….’ message is shown. Now release the select button. The procedure is complete.

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