Voltage sensitive fridge relay faulty

Ardsboy11 replied on 08/04/2021 09:00

Posted on 08/04/2021 09:00

Last year I got good advice here on how to set the relay cut out and all was fine until my CRV went to Honda for it's annual service 2 weeks ago. The dealer said the battery was low so it was put on charge during the service. About a week later starting seemed a bit sluggish I checked the voltage and it was 12.2. ( battery not long new and fitted by Honda as car has stop /start system).

I then checked the number 10 socket and found that the relay did not cut out until the voltage dropped to 12.28v at the battery.

So Is this draining my battery down as there is a parasitic drain, (previously detected prior to last year's reset)

Is the relay faulty, and 

Finally should Inreplace the relay with one that is preset to cut in at 13.5v and cut out at 12.8v. Available from accessory shops online.

EmilysDad replied on 08/04/2021 10:57

Posted on 08/04/2021 10:57

is there not the option to tweak the relay? Some have a potentiometer on them to allow you to adjust the point at which they trigger

LLM replied on 08/04/2021 11:22

Posted on 08/04/2021 11:22

The fridge is cannot drain the car battery unless the caravan and car are connected and the car engine is not running.  How often is that the situation and for how long?

Whatever the situation you should charge the car battery.

Ardsboy11 replied on 08/04/2021 13:13

Posted on 08/04/2021 10:57 by EmilysDad

is there not the option to tweak the relay? Some have a potentiometer on them to allow you to adjust the point at which they trigger

Posted on 08/04/2021 13:13

Yes, there is. It was adjusted last summer in accordance with advice given. Now however if the battery has a resting voltage above 12.28 the number 10 stays live until the parasitic drain pulls the voltage down.

Ardsboy11 replied on 08/04/2021 13:18

Posted on 08/04/2021 11:22 by LLM

The fridge is cannot drain the car battery unless the caravan and car are connected and the car engine is not running.  How often is that the situation and for how long?

Whatever the situation you should charge the car battery.

Posted on 08/04/2021 13:18

The caravan is not connected, I think that despite previously adjusting the VSR it must have gone off setting and I am considering replacing it with a factory set one with cut in at 13.5 and cut out at 12.8V.

EmilysDad replied on 08/04/2021 13:58

Posted on 08/04/2021 13:58

but as LLM says, no matter what voltage it opens & closes, if there's nothing plugged into the socket, then I'm not sure how the relay is the cause of your battery being discharged. But can you not tweak the relay again so that it needs more than 12.7 volts before it closes ie when the engine is running

Ardsboy11 replied on 08/04/2021 15:35

Posted on 08/04/2021 13:58 by EmilysDad

but as LLM says, no matter what voltage it opens & closes, if there's nothing plugged into the socket, then I'm not sure how the relay is the cause of your battery being discharged. But can you not tweak the relay again so that it needs more than 12.7 volts before it closes ie when the engine is running

Posted on 08/04/2021 15:35

This what I am thinking, just take some time as most of the trim will have to come off in the rear inside quarter to get at it. 

Thanks to all for the comments and advice.

LLM replied on 08/04/2021 15:48

Posted on 08/04/2021 13:58 by EmilysDad

but as LLM says, no matter what voltage it opens & closes, if there's nothing plugged into the socket, then I'm not sure how the relay is the cause of your battery being discharged. But can you not tweak the relay again so that it needs more than 12.7 volts before it closes ie when the engine is running

Posted on 08/04/2021 15:48

As you say ED an open circuit can't drain the battery. The trip voltage of the relay is just a red herring.  I wonder how long the car was sitting unused and unconnected prior to the OP finding the low battery voltage.  

Ardsboy11 replied on 08/04/2021 18:53

Posted on 08/04/2021 15:48 by LLM

As you say ED an open circuit can't drain the battery. The trip voltage of the relay is just a red herring.  I wonder how long the car was sitting unused and unconnected prior to the OP finding the low battery voltage.  

Posted on 08/04/2021 18:53

2 days and it is garaged.

LLM replied on 08/04/2021 19:57

Posted on 08/04/2021 18:53 by Ardsboy11

2 days and it is garaged.

Posted on 08/04/2021 19:57

Whether it's garaged or not is most probably irrelevant.  I would be looking for a drain such as an internal lamp, perhaps the boot light, roof light or maybe the glove box lamp.  Failing that it needs to go to the agent for a check con their diagnostic kit.

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