Low Battery Warning Fix

The Revo's OptiDrive unit is much better than the clunky reversing setup found in the T-Maxx. There are many misconceptions that are floating around about it, such as that it controls shifting between first and second gears, and that it's also a failsafe. However, the reality is that many people are just mistaken or misinformed. The OptiDrive unit only controls forward to reverse shifting, and it only monitors battery voltage. It does not act as a failsafe.

There is one area that I've often seen referenced that does bear some explaining. That's the "low voltage" indicator on the OptiDrive. This flashing light sequence, which is explained in your manual, indicates that the receiver pack is nearly depleted. It works weel in most cases. However what many people have discovered is that when the stock receiver is changed out for an aftermarket one, such as a JR, the low battery warning flashes even with a full charge.

The reason for this is that some receivers lower the battery voltage on the servo outputs. Since the OptiDrive is plugged into the output for servo channel #2, it sees this lower voltage and thinks it means the receiver pack is nearly depleted. The cure for this is simple, and all that's needed is a servo Y-harness, such as this one from Traxxas.

The first thing you'll need to do is to open the receiver box and spread out the wiring contained in it, allowing you to see what you're working on.

The next thing you'll need to do is to unplug the battery from the receiver, and then unplug one of the servos. I chose to unplug the servo on channel 2, which is the throttle servo. The other channels would work as well, but for simplicity I didn't want to use the steering channel because that would mean would be plugging a y-harness into a y-harness. I feel that just gets too messy. If you have eliminated reverse and are not using channel #3, you could use that channel and not even need the y-harness. In that case, simply plug the battery into channel #3.

Next, plug the servo and the battery plugs into the y-harness. Make sure you have plugged them in correctly and not reversed their orientation.

Finally plug the male end of the harness back into the receiver. It should pug into the servo channel you unplugged earlier. Keep in mind if the wiring harness you are using uses Futaba plugs, and you are using a non-Futaba style receiver, you may find it necessary to trim the plug as shown on my servo page here. If you don't want to have to trim the plug, you might want to consider using this harness instead.