Discussion:
Toyota 7FGCSU20 Serial# 69829

Battery is being drained due to a draw. Have to disconnect the alternator and the controller mounted inside the battery box to remove the voltage draw of 9 volts. Must disconnect both, either one hooked up and the draw is still there. Has anyone had this problem before? What does the controller in the battery box do? Are we missing something in the harness that could cause this problem. We have gone step by step disconnecting everything from the key switch, all the fuses and relays. Customer has been jump starting machine due to dead battery. Thanks for all the help.
  • Posted 17 Mar 2012 04:45
  • By garland_m
  • joined 16 Oct'09 - 205 messages
  • Virginia, United States
Work Hard and Fish Long
Showing items 1 - 8 of 8 results.
I belive that the controller is in the box. I think that one of our techs has had issues with the wiring harness rubbing throught where it enters the box.
  • Posted 21 Mar 2012 12:36
  • By rogeriwt
  • joined 10 Apr'07 - 323 messages
  • Massachusetts, United States
s in model number designates space saver model with shorter counterweight and I am not quite sure what controller in battery box does unless unit is equipped with TWC system for emissions and is silver in color. I would imagine that alternator is your problem or harness itself damaged.
  • Posted 21 Mar 2012 11:50
  • By Huckleberry
  • joined 20 Jul'11 - 29 messages
  • Tennessee, United States
I think you and I are looking at the problem from two different points of view, you have stated that you have nine volts constant and Im asking what is the current draw its the current draw thats flatening the battery not the voltage, I respect your thirty years in the lift truck bussiness, Ive had thirty six years mainly on electric truck.

Titus
  • Posted 19 Mar 2012 01:56
  • By Titus
  • joined 6 Jul'10 - 185 messages
  • North Yorkshire, United Kingdom
I noticed the S in the model #- is this a safety rated truck? If you disconnect the little box in the battery box but leave the alternator hooked up I understand you still have a voltage draw, but will the truck still run? Does the alternator still charge? What electrically is affected?
  • Posted 18 Mar 2012 12:06
  • By bbforks
  • joined 1 Mar'12 - 1,437 messages
  • Pennsylvania, United States
bbforks (at) Hotmail (dot) com
Customers love technology- until they have to pay to fix it!
generally if there is a draw on the system through the alternator its most likly caused by a shorted regulator, if its internal to the alternator and not that little box on the battery u spoke of earlier then have the alternator checked and repaired.
If indeed that little box has something to do with the regulator then replace that too.

Just my guess
  • Posted 18 Mar 2012 08:00
  • By Jplayer
  • joined 12 Apr'07 - 407 messages
  • North Carolina, United States
John Player Jr
_________________
LiftOne, LLC
Charlotte, NC
Email: jplayer@liftone.net
Is there any accessories on the machine, like a Shock Watch? Looking at a schematic the only things "powered up" with the key off are the light relays, horn, cable to the starter, cable to the alternator, and the S terminal on the plug that goes in the alternator (5 amp alt. fuse in the fuse box).
  • Posted 18 Mar 2012 01:33
  • By mrfixit
  • joined 11 Dec'08 - 1,434 messages
  • New York, United States
Titus,

We have already verified the amperage draw. The battery has been checked as this would be the first thing to do. Been i this buisness for over thirty years. Appreciate the suggestion but haave been there. My biggest concern is replacing just the alternator will not reduce the draw. Want to make sure we are not missing something that has happened before. Thanks.
  • Posted 18 Mar 2012 01:13
  • By garland_m
  • joined 16 Oct'09 - 205 messages
  • Virginia, United States
Work Hard and Fish Long
Im not familliar with this truck but Ive given it some thought and i think at this stage you need to put your digital meter on the amps range and check the current draw from the battery insert it between the battery positive post and the cable terminal and read of the current draw if its ten amps you have a problem if its.0100 amps then theres no problem and the battery is past its best and needs replacing. Better still charge the battery up and do a load test on it How old is the battery. I think you need to check the battery capacity before you go looking for current and earth leakage.


Titus
  • Posted 17 Mar 2012 21:26
  • By Titus
  • joined 6 Jul'10 - 185 messages
  • North Yorkshire, United Kingdom

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