battery doesn't seem to be charging while driving

N7SHG_Ham

The following has nothing to do with this thread EXCEPT to wonder why some manufacturers do NOT provide a proper seven way. Even if you get a so called tow package, you still can't tow without rigging up a seven way. I mean to me it seems logical if they really intended for a vehicle to tow anything over 1000 pounds, why don't they include what you need to do that? Are certain manufacturers just saying in marketing materials it is rated to tow xyz and memo is not making it to engineering and production so the vehicle can be equiped to do so? If I bought a vehicle and had to rig something up like the OP did, I would NOT be happy. Obviously the manufacturer had no intention of the end user towing anything that requires brakes or a charge line.

ChanW

@GrandmasKid, I think what @Marceline is suggesting is that you could install an aftermarket 7 pin receptacle on your Highlander.  It would be tidier (& more reliable) than having the combination of the 4pin and 7pin, as you do.

It sounds like you already have the necessary wires back there, so it would just be a matter of removing the 4pin connector and reconnecting those wires (and the heavier charge wires) to the new 7pin connector.

The problem I had (and still do) is that the bracket that eTrailer provides with their 7pin  receptacle is extremely rust-prone, as it has a lousy paint job on it. I think I tried two different brands and each was a letdown.

So if you do go with an aftermarket mounted 7pin receptacle, I highly recommend you give the bracket a good coat of paint before you mount it!

GrandmasKid

Marceline said:

GrandmasKid said:

There is a difference between the hybrid and non-hybrid. The hybrid models are only rated to tow up to 3,000 pounds and the gas models to 5000 pounds mostly due to the lighter duty CV transmission I think. I'll look again but I don't believe anyone sells a 7way harness for my Highlander Hybrid, and I have looked at Etrailer. The hybrid doesn't have a traditional alternator but instead uses a controller that controlls the charge from the big drive battery bank to the starter battery and the wiring for the harness is different between the two types of Highlanders. I think that my new setup will be fine as long as I keep the contacts protected. I’ll let you know. 

Unlike other online merchants, I’ve found the people at eTrailer to be pretty knowledgeable. I think that it would be worth your while to read the info at the link I posted above and then contact them with your hybrid-specific questions. The 4-pin to 7-pin hardwire adapter that they sell (https://www.etrailer.com/p-ETBC7.html) isn’t Toyota-specific, but I bet that you can install it on your vehicle (here’s info about installing it in a 2017 Highlander Hybrid: https://www.etrailer.com/question-368132.html).

Are you using a wireless brake controller? 

Sorry if I haven't been clear. I have installed an adapter not made by toyota that replaces the corroded one I had. There are lots of such adapters available. I am using a Prodigy wireless brake controller that is now working fine.

GrandmasKid

Marceline said:

GrandmasKid said:

There is a difference between the hybrid and non-hybrid. The hybrid models are only rated to tow up to 3,000 pounds and the gas models to 5000 pounds mostly due to the lighter duty CV transmission I think. I'll look again but I don't believe anyone sells a 7way harness for my Highlander Hybrid, and I have looked at Etrailer. The hybrid doesn't have a traditional alternator but instead uses a controller that controlls the charge from the big drive battery bank to the starter battery and the wiring for the harness is different between the two types of Highlanders. I think that my new setup will be fine as long as I keep the contacts protected. I’ll let you know. 

Unlike other online merchants, I’ve found the people at eTrailer to be pretty knowledgeable. I think that it would be worth your while to read the info at the link I posted above and then contact them with your hybrid-specific questions. The 4-pin to 7-pin hardwire adapter that they sell (https://www.etrailer.com/p-ETBC7.html) isn’t Toyota-specific, but I bet that you can install it on your vehicle (here’s info about installing it in a 2017 Highlander Hybrid: https://www.etrailer.com/question-368132.html).

Are you using a wireless brake controller? 

Sorry if I haven't been clear enough. I have already installed an adapter that appears to be working well. If I get time tomorrow I'll measure the current to the T@B battery  with the Norcold refrigerator turned on. I did look at the Etrailer linked site and what they suggested is almost exactly what I did. Thanks for your input.