Trickle Charger/Gauges Blown

[sethgt]

Hi,
After reading the many posts concerning gauge problems, and having just replaced my oil pressure gauge, I have a question about using a trickle charger. I bought the Battery Tender from Cool Tech, but have not used it yet. I have a brand new battery that was just installed by a Ford SVT dealer. The gauge was not functioning prior to the battery replacement. I discussed all the posts concerning battery surge, trickle charging, etc. causing gauges to fail with the GT trained mechanic at the dealer. He told me to never plug the Batery Tender directly into the socket on the dash board, and told me to buy an accessory outlet with battery terminal clamps. I bought one from Radio Shack. He said to then remove the negative battery cable, plug the tender into the accessory outlet, and then attach the terminal clamps to the battery. That way, the tender is hooked directly up to the battery, and not cycling through the cars electronics. Has anyone had a blown gauge using a tender this way, or were the blown gauges all from plugging directly into the socket on the dash inside the car? On my Z8 I have always plugge into the cigarette lighter socket, and never had any issues.

Thanks,
Seth

 

[GT35065]

There have been blown guages from plenty of people who never used trickle charger from what I have read on this forum.

 

[nota4re]

Seth,

You are not the first to contemplate a potential relationship between charging of the battery and the gauge failures. I, like many others, have attempted to read every post regarding the gauge failures and my conclusion is that there is no indication of a relationship between the two. For the sake of everyone, I wish there was - so that we could finally corner and solve this elusive gauge anomoly.

Regarding the float chargers that we sell (Battery Tenders), our most popular kit is the in-car kit that direct connects to the battery and offers an accessible "ChargePort" for the owner to plug in the car (hidden in the nose nearby the tow hook nut). Our "generic" kit is very similar to Ford's OEM solution and that plugs into the "always hot" cigarette lighter. The Battery Tenders have superior on-board electronics as compared to the OEM unit - but neither of these units nor various others that owners have used can be isolated down to the gauge failure.

My theory is that there is some kind of specification incompatibility between the gauge control module (built by one vendor for Ford) and the gauges (built by another vendor for Ford.) Something coming from the gauge control module is knocking out the gauges - but it is difficult to determine if the "fault" is with the control module or the gauges themselves.

I think we have more information coming soon. We have two gauges with a repair facility now and are awaiting their feedback as to what part of the gauge failed. Perhaps that can provide further clues.

In the interim, I would recommend owners to continue to use the float charger of their choosing as this will help to prolong the life of the battery.

As for the recommendation you received from a dealership "GT Tech", I do NOT like his procedure of disconnecting and reconnecting the battery each time you store the vehicle. Not only do you reset the ECU each time (not as big of a deal as the internet chat would have you believe), but you are also causing some spikes each time you re-connect the battery. I would say that this method is not only more time consuming for an owner, but it also may provide more exposure for problems. Follow Ford FACTORY advice, and simply hook up your charger of choice. I'm not sure if it's necessary, but you can always get in the habit of connecting the float charger of the car FIRST and then connecting it to the wall SECOND.

 

[sethgt]

Trickle charger

Thanks for the response. I understand that gauges have been blown when owners did not use the trickle charger as well as with the charger. It seems that low batteries can cause the surge that casuses damage, that is why I want to be cautious and use the tender correctly. I took delivery of my car on 3/31/2010. I immediately noticed the oil pressure gauge stuck on zero. Tried changing the sending unit, but nothing. The Ford SVT tech was able to see that there was an electronic surge at some past point. Probably from a jump start prior to sending the car from the dealer in Houston, to me in New Jersey. As mentioned I had the Ford dealer replaced the battery with the most up to date Ford GT battery. Gauge also now replaced and working.

 

[RALPHIE]

...I'm not sure if it's necessary, but you can always get in the habit of connecting the float charger of the car FIRST and then connecting it to the wall SECOND.

I believe that this is the recommended procedure that came with the float charger I got from you, and I always use this sequence. I have had no gauge problems (knock on wood) either before I started using a Battery Tender, or since.

 

[GEE-TEE]

I believe one of the gauges mentioned in repair might be my old Boost Gauge. I was using the OEM charger before and one day the thing was just stuck. I dont know if there is a relation but I replaced the gauge at Cooltech and also am now using the charger from them which is ideal and plugs right in from the front air scoop. Fingers crossed no more gauges will go anytime soon.

So, do you also recommend unplugging from wall before unplugging from car?

 

[DWR46]

All of this advice is correct. Hook the Battery Tender of your choce directly to the battery terminals. Always plug the tender into the wall outlet last and unplug it from the wall outlet first. I know nobody seems to want to hear this, but junk the Optima battery and get a standard discount store battery. No more gauge problems, and the battery holds a charge for a long time without requiring a tender.

 

[nota4re]

The Ford SVT tech was able to see that there was an electronic surge at some past point.

Don't believe everything you are told :wink

 

[RALPHIE]

...So, do you also recommend unplugging from wall before unplugging from car?

Yes

 

[paul b]

If any of this is correct, Ford should make good. Ford supplied the charger and directions or lack of them.