TX GX460
Moderator
I spend most of my time in the GX/Prado forum, but wanted to point out a few issues I have run into with using AGM batteries in my wife's LC 200 and how we solved them. I also wanted to make everyone aware of a new voltage booster product for the 200 series that was just released and has worked well for me.
I added a dual battery setup to the 200 series several years ago. I used the Cruiser Outfitters Group 31 battery box, the Odyssey Extreme AGM group 31 and 34 batteries for starter and house, respectively, and the Cruiser Outfitters aluminum terminal extensions for the group 31.
I purchased a mini blade fuse diode alternator voltage booster from an Australian supplier. Unfortunately, it only boosted the alternator to between 13.5V and 13.8V, with rare increases to 14V. It wasn't optimal, but I made due with little else available at the time.
After a few years, I started having regular but intermittent starting problems, including just after full battery charging. I would often have to connect the house battery to jump the motor. After a few battery replacements and three different shops looking at it, the team at Tandem Automotive in Fort Worth figured out that the metal differences between the extension (aluminum), terminal block (lead), and bolt (steel) had caused significant joint corrosion such that current was unable to get through much of the time. An example of the corrosion is below. Although it could have been lessened by more liberal application of dielectric grease, corrosion would have likely still occurred.
The stock battery cables were too short to use without extensions and I did not want this happening again, so I had Tandem do a 0 gauge replacement on the starter, ground and alternator wires (I realzed there are other ways to do an extension but I wanted a robust solution). Tandem also fabricated a custom mount for the ARB compressor and a new fuse/distribution panel. The effect has been noticeable, with a noticeably faster and stronger start and no more starting or charging issues.
The other thing I wanted to change was the voltage booster. For AGM, I wanted to charge at closer to 14V, and preferably a little over. I also was not too fond of a diode in place of a fuse for the alternator. The best solution I found was by Voltage Booster Pro here in Texas, but unfortunately they did not have anything for LC200s. However, Bryan at VBP was super nice when I reached out to inquire about LC200 solutions and he worked with me to create a solution that worked with my wife's vehicle (he had to modify the design for the Tundra due to a slightly difference in fuse and relay locations). It has a separate, replaceable fuse in line with the diodes, and also has a selectable "low" and "high" booster option, depending on your needs or battery type. It is called the "Spark" model, and Option "A" in the pull-down menu is for the LC200 (Voltage Booster PRO "Spark" (2nd Gen Tundra, 2nd Gen Tacoma, 2nd Gen Sequoia, LX570) - https://voltageboosterpro.com/product/spark/). The cost is a little higher than diode fuse options, but given the better safety and reliability (as well as the cost for having custom circuit boards made) I think the difference makes sense.
I am now getting around 14.2-14.3V at startup and 14V at warm idle on the "high" setting (I have not tested the "low" setting). Overall I am much happier with this solution and hope that it will provide me much better charging and longevity for the AGM batteries. I also like supporting a US-based company who does their own engineering work and has great support for enthusiasts.
I hope what I have learned and discovered is helpful to others on the forum.
I added a dual battery setup to the 200 series several years ago. I used the Cruiser Outfitters Group 31 battery box, the Odyssey Extreme AGM group 31 and 34 batteries for starter and house, respectively, and the Cruiser Outfitters aluminum terminal extensions for the group 31.
I purchased a mini blade fuse diode alternator voltage booster from an Australian supplier. Unfortunately, it only boosted the alternator to between 13.5V and 13.8V, with rare increases to 14V. It wasn't optimal, but I made due with little else available at the time.
After a few years, I started having regular but intermittent starting problems, including just after full battery charging. I would often have to connect the house battery to jump the motor. After a few battery replacements and three different shops looking at it, the team at Tandem Automotive in Fort Worth figured out that the metal differences between the extension (aluminum), terminal block (lead), and bolt (steel) had caused significant joint corrosion such that current was unable to get through much of the time. An example of the corrosion is below. Although it could have been lessened by more liberal application of dielectric grease, corrosion would have likely still occurred.
The stock battery cables were too short to use without extensions and I did not want this happening again, so I had Tandem do a 0 gauge replacement on the starter, ground and alternator wires (I realzed there are other ways to do an extension but I wanted a robust solution). Tandem also fabricated a custom mount for the ARB compressor and a new fuse/distribution panel. The effect has been noticeable, with a noticeably faster and stronger start and no more starting or charging issues.
The other thing I wanted to change was the voltage booster. For AGM, I wanted to charge at closer to 14V, and preferably a little over. I also was not too fond of a diode in place of a fuse for the alternator. The best solution I found was by Voltage Booster Pro here in Texas, but unfortunately they did not have anything for LC200s. However, Bryan at VBP was super nice when I reached out to inquire about LC200 solutions and he worked with me to create a solution that worked with my wife's vehicle (he had to modify the design for the Tundra due to a slightly difference in fuse and relay locations). It has a separate, replaceable fuse in line with the diodes, and also has a selectable "low" and "high" booster option, depending on your needs or battery type. It is called the "Spark" model, and Option "A" in the pull-down menu is for the LC200 (Voltage Booster PRO "Spark" (2nd Gen Tundra, 2nd Gen Tacoma, 2nd Gen Sequoia, LX570) - https://voltageboosterpro.com/product/spark/). The cost is a little higher than diode fuse options, but given the better safety and reliability (as well as the cost for having custom circuit boards made) I think the difference makes sense.
I am now getting around 14.2-14.3V at startup and 14V at warm idle on the "high" setting (I have not tested the "low" setting). Overall I am much happier with this solution and hope that it will provide me much better charging and longevity for the AGM batteries. I also like supporting a US-based company who does their own engineering work and has great support for enthusiasts.
I hope what I have learned and discovered is helpful to others on the forum.
