2026-01-31
Now that we have ordered a caravan, I need to get the Prado ready to tow it. When we hired a van in Tasmania, it was an older Jayco with nothing special with regards to onboard electrics. It wasn't set up for off-grid camping beyond having a three way fridge and gas cooktop/grill. So a standard 7 pin trailer plug was all I needed for that trip. We also weren't doing large distances, and the weather was cold, so keeping the fridge going while on the road wasn't a huge concern.
However, the new van has a 120Ahr AGM battery and 200W of solar cells to recharge it in camp. We'll also be doing considerably more distance in much higher temperatures. To keep the caravan battery charged while we're on the road (and thus the fridge going), we need an Anderson plug (grey) wired back to the car battery. As it turns out, the ESC (electronic stability control) also needs its own Anderson plug (a red one). So I set about aquiring the bits and pieces for me to install that myself.
I opted for a Kings Anderson plug kit for the grey plug, as it was pretty much all inclusive, minus the VSR (voltage sensitive relay) which I added to the circuit so the caravan doesn't drain the starter battery if the engine isn't running. For the red anderson plug, I put in a 60A breaker to act as fuse and manual switch if needed.
With my kit pretty much ready, it was time to do the install. First task was to find somewhere to mount the VSR and Breaker in the engine bay, not far from the battery. It turned out there was a handy spot with a couple of M8 threaded holes just under the gas strut for the bonnet, so I fabricated a bracket out of stainless steel and mounted both devices. It turned out to be nice tidy, accessible solution.
Next I encased all the wires inside some 22mm split tube (cutting my thumb up somewhat in the process), and spent a lot of time under the car routing the cable bundle to the rear, avoiding moving parts and hot parts and using cable ties to secure it so it could not move or snag. I had just enough cable to do the run (6m). The anderson plugs were then wired up, and mounted to a brass shim which was then screwed to the tow bar rail next to the 7 pin socket.
