2015 Honda cr-v 2.2 - Towing problem

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Thu 10 Sep 2015 21:59
2015 Honda cr-v 2.2 - Towing problem - steelman

When towing a caravan the fridge relay is intermittantly on and off.

Is there a problem with the alternator output. Have heard that Honda automatically reduce the voltage under low load conditions. Is this correct and if so, is there a solution?

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Thu 10 Sep 2015 22:22
2015 Honda cr-v 2.2 - Towing problem - RT

Quite a few modern cars have "smart" alternators which reduce the voltage according to throttle position. The traditional smart relay for caravan wiring isn't nearly smart enough and either cycles on/off at low frequency or chatters at higher frequency. Smart caravan relays can be adjusted but not low enough to avoid the problem, and if they could they'd stay on when the engine is switched off !

I resolved the problem by having a Durite 140A VSR fitted which styays latched once triggered.

It's ludicrous that towbar fitters haven't yet woken up to the problem, it's been around nearly 2 decades on some models.

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