OK, I know this isn't the Excursion forum, but it gets more attention/readers, so...
Batteries go dead overnight on my '03 7.3L Ex box. Charging voltage is 14.3+, and near dead battery voltage is 12.2 v. After several hours of charging the beast starts right up, and I can drive it normally all day, with several start/stop cycles. Only aftermarket goodies installed are Edge CTS monitor and DP tuner. They have been in for 2 years, and problem arose recently.
Checked current draw with both batteries disconnected, let module sleep first. Fuse 35 - instrument cluster - pulls 5.3 amps, AMPS not milli-amps! Without fuse 35, total draw is about 20 ma.
Would appreciate advice as to what is next logical step to test.
I understand that the cluster is related to a battery saver and/or GEM module, but not sure of specifics for this year.
Any tips on what test process to follow or what to check next from here?