Toyota 4Runner - DC from 7 pin connector

**Denny_A** · 09-04-2003, 03:28 PM

I now have a 2000 Toyota 4Runner. The dealer had the 4 pin connector replaced with a Bargman 7 pin. When I checked the DC power pin (#4) - there was no voltage under any condition.

Called the dealer and informed them. Turns out the job was outsourced to a truck mod/maintenance shop (good rep). Apparently, they assumed only the original 4 pins needed power.

Dealer sent me to them to finish the job. They used a 20 amp resetting CB (ok, right?). When I checked the Pin #4 at home, it is powered continuously. No isolation when the ignition is off and engine stoped.

Question to 4Runner/Toyota experts - is this right? I don't think so, but wouldn't want to place any bets. I don't want to have to install a Batt Isolater if it's not needed.

Thanks - Denny_A

**Civil_War_Buff** · 09-04-2003, 03:34 PM

Denny,

A 20A c/b might be a little under spec'd, but as for power constantly, that should be correct. When I installed the fuse to my Tahoe (per the owners manual), I have 12VDC at the connector pin at all times as well. There is no draw as long as you are not hooked up, but it is not a switched connection. I imagine that you could switch it if you wanted to, but I doubt that it would be necessary. I hope that Mike will give us his wisdom on the matter as well.

Larry

**Denny_A** · 09-04-2003, 07:28 PM

[quote author=Civil_War_Buff link=board=20;threadid=1271;start=msg8838#msg8838 date=1062707675]
Denny,
When I installed the fuse to my Tahoe (per the owners manual), I have 12VDC at the connector pin at all times as well. There is no draw as long as you are not hooked up, but it is not a switched connection.
Larry
[/quote]

Thanks Larry. I probably should have clarified the question more fully in the original post.

The issue of an always hot DC connection is related to parking the trailer and TV with the reefer running on DC. Some have been chagrined to discover the TV battery to have been drained while they were away a bit longer than anticipated. I picture having to disconnect the Bargman at each rest stop - and forgetting to reconnect just once.

My Honda Odyssey was never a problem, but I confess I never took the trouble to actually test it. Maybe I was just lucky.

So, I'm still wondering if anyone has the info about a 4Runner or any comparable Toyota.

The question: Is the 4Runner supposed to isolate its battery (no DC to pin #4) when the keys are removed from the ignition switch?

Thanks -- Denny_A

**Denny_A** · 09-05-2003, 10:15 PM

I found the answer - probably.

According to the mechs at both a camper repair shop and truck mod shop, Toyota SUV's and trucks do not have a battery isolator, such as that in Fords. Exception is the Toyota Tundra with a factory installed towing package. Toyota service peeps also said the factory tow package for trucks and SUV's includes only a straight 4 pin connector.

Hearsay, of course, but it is likely to be correct, methinks. So, I'll either have to be aware of the hot DC connection and not park and sight-see several hours enroute, or disconnect the electric connection, or invest in a battery isolator (bookmarked a couple of sources last yr) if I want total peace of mind.

Denny_A

09-08-2003, 06:42 AM

Hey Denny,

Keep us posted as to how the 4Runner tows... After our various prior posts & discussions, I would be interested to hear your feedback!

Steve

**Denny_A** · 09-08-2003, 11:57 AM

[quote author=Steverino link=board=20;threadid=1271;start=msg8950#msg8950 date=1063021323]
Hey Denny,
Keep us posted as to how the 4Runner tows... After our various prior posts & discussions, I would be interested to hear your feedback!
Steve
[/quote]

Wilco! I should be heading out in about two weeks for 10-14 days to the Badlands and Black Hills (800 mi.). Report to follow upon return.

I am thinking about adding a supercharger to bump the HP up to 251. At $2500 + installation, Ms Teddy said....... ummm.... can't repeat it in this forum. :-X

Denny_A

P.S.: So far, I love this truck. Shakedown will see if it loves my TM! :

**Bill** · 09-08-2003, 05:16 PM

Denny -

You are more than capable - why not just bite the bullet and install an isolator relay? They are readily available and easy to install. Probably would take less time than all the go-arounds you had with Toyota.

My Explorer has an isolator relay as part of the factory towing package. I think it is great - I never have to worry. I don't think I would want a diode isolator. I've never understood why they don't result in an undercharged battery, although I'd like to be educated.

If you have questions, e-mail me privately.

Bill

**Denny_A** · 09-08-2003, 08:09 PM

[quote author=Bill link=board=20;threadid=1271;start=msg8986#msg8986 date=1063059381]
Denny -

--------.--------snip--------.----------
My Explorer has an isolator relay as part of the factory towing package. I think it is great - I never have to worry. I don't think I would want a diode isolator. I've never understood why they don't result in an undercharged battery, although I'd like to be educated.

Bill
[/quote]

Bill,

Any comments about the Hellroaring Isolator? --> here:

http://hellroaring.com/nodiode.htm

I've had it bookmarked since the big isolator discussion last year. Has diodes, but they say not the voltage drop and loss of charging potential. Just curious- seriously curious.

Denny

**Bill** · 09-08-2003, 08:47 PM

The product might or might not be good, but there isn't enough info to know. They carefully hide anything meaningful. And there are enough lies and obfuscations to make me distrust them. I personally would not send a check.

1. I agree with them about the problems with diode isolators. They suggest that the solution is a remote-sense voltage regulator, and I agree, but I have never seen a regulator with this capability. If so, this would be the ideal solution - but I think they have suggested it as a red herring, so you will be disappointed if you try to go down this road.
2. Their page about the disadvantages of relays is ludicrous (private email for details if desired). For this reason, I distrust their entire spiel.
3. They tell you in great detail what the other ("old&quot

approaches are to isolation, and they shoot down each of them. But they never get around to telling you what their approach is, so you can compare. This kind of obfuscation is another reason to distrust, IMHO. They may be using power FETs, which would be good - but if they are doing this, why not say so?
4. The cost - about $150 - is very high compared to a relay - about $10. Relays are a mature technolgy, inexpensive by virtue of their maturity and volume production, good for thousands of operations, and really ideal for the application.
5. Contrary to their assertion, relays consume no power in the OFF state (when it matters). This misleading statement, among others, continues to lead me to distrust them.

Wanna buy a bridge?

Bill

**Denny_A** · 09-08-2003, 09:24 PM

[quote author=Bill link=board=20;threadid=1271;start=msg9006#msg9006 date=1063072073]
The product might or might not be good, but there isn't enough info to know.
--------------snip---------
5. Contrary to their assertion, relays consume no power in the OFF state (when it matters). This misleading statement, among others, continues to lead me to distrust them.

Wanna buy a bridge?

Bill
[/quote]

Thanks, but I already have one - don't need a spare! :P

Oh, and $10 does sound better than (gulp) $150.

Thanks,

Denny (MSAE, PhED*)

*Dr. of Electrical Doofusry ???