Nevada_545 - we measured the charging voltage at the 7-pin plug at the back of the Colorado (measuring voltage between the battery charge and ground pin)s. We observed no difference in charging voltage when we engaged and then disengaged Tow/Haul Mode several times. It appears that alternator output is governed solely by the charge level of the Colorado’s battery. If it’s charged up, alternator output is limited to 12.8 volts. When the Colorado’s battery charge level drops, alternator output kicks up to 14.5 volts.
Cougar - we measured wire losses from the Colorado battery posts to the 7-pin plug at the back of the truck, using a strand of heavy gauge wire from the battery posts to the back of the truck so we could use a single multi-meter. Very low resistance was observed (0.006 ohm, I believe). The camper has been used with three tow vehicles other than the Colorado and recharges effectively with each of the other three vehicles. We’ve also recharged the camper battery with two different trickle chargers and via the 30-amp AC cord on the camper itself. We purchased a battery load tester near Rocky Mountain National Park and found camper battery health to be good after trickle charging or using the AC power cord to charge the battery. The morning after our refrigerator quit working, the camper battery showed just under 11 volts and good response to a 10-second load test.