OFFROADSUBARUS.com

Go Back   OFFROADSUBARUS.com > Technical Forums > General Troubleshooting and Technical Help

Notices

User Tag List

Reply
 
Thread Tools
  #1  
Old 4th February 2017, 08:06 PM
Ratbag's Avatar
Ratbag Ratbag is offline
Administrator
 
Join Date: Jan 2012
Location: Bayside, Melbourne, Vic
Year: MY06, MY10
Model: Forester SG & SH
Transmission: 5MT/DR & 4EAT Sports
Posts: 6,198
Ratbag is on a distinguished road
Default The case of the misbehaving central locking

Gidday All

Roo2 (2006) developed a strange misbehaviour relating to the key activated central locking about 6 months or so ago.

Periodically, it would require a second press on the key button to lock/unlock the car. Sometimes (rarely) would not work at all. This got progressively worse, and more annoying, over that time until about 2 weeks ago, when my key stopped working most of the time. Had to lock/unlock the car using the physical key/lock and the internal car lock/unlock button.

[EDIT] Interestingly, it almost always worked fine in the afternoons, just not first thing in the morning, progressively worsening. I realise now that this was due to the battery becoming slightly warmer, and therefore having a slightly higher nominal voltage ... [end edit]

Visions of a new central locking unit and $$$ ...

Pinched my wife's key, and all was good again. Worked perfectly!

Pulled both keys apart, and measured the battery voltages. My key was 2.997V; wife's was 3.064V. Both no load voltage, so less than 0.1V difference between them.

Bought a couple of new 1620 batteries. Measured them. No load voltage is 3.315V for each new cell.

Changed both batteries (as ten y.o.) and all is sweet again .

What really surprised me is the extremely fine operate/not operate tolerance between the two exhausted batteries.

Last edited by Ratbag; 4th February 2017 at 08:48 PM. Reason: obvious ...
Reply With Quote
  #2  
Old 4th February 2017, 09:06 PM
Kevin's Avatar
Kevin Kevin is offline
Administrator
 
Join Date: Jul 2008
Location: Sydney, Oz
Year: MY'03
Model: Forester
Transmission: A/T
Posts: 4,220
Kevin is on a distinguished road
Default

You bet - a common problem! Further discussion here: http://www.offroadsubarus.com/showthread.php?t=5493

I've found the Panasonic batteries are good


Also long story short: I couldn't open my doors after skiing at Perisher a few years ago; had to use the door key and set the alarm off. Had a flashing alarm light all the way down into Jindabyne where, once warmed up, the car gave a couple of beeps accompanied by light flashes and all reset to normal.
__________________
MY'03 Foz AT XS with centre lock-up
MY'10 Triton AT GLX-R 2.5 DiD
www.subaruclub.com.au
Reply With Quote
  #3  
Old 4th February 2017, 09:57 PM
Ratbag's Avatar
Ratbag Ratbag is offline
Administrator
 
Join Date: Jan 2012
Location: Bayside, Melbourne, Vic
Year: MY06, MY10
Model: Forester SG & SH
Transmission: 5MT/DR & 4EAT Sports
Posts: 6,198
Ratbag is on a distinguished road
Default

Thanks, Kevin. I've tagged the older thread with all the same tags as this one.

The replacement batteries I bought are Maxell, with an expiry date of 2020.

I just measured some dry cell batteries that had an expiry date of 2000. One was leaking; both were over nominal voltage still! Not bad going ...
Reply With Quote
  #4  
Old 4th February 2017, 10:44 PM
duncanm's Avatar
duncanm duncanm is offline
Senior Member
 
Join Date: Sep 2014
Location: Sydney
Year: 1998
Model: Outback. JDM TT conversion
Transmission: 5MT DR
Posts: 462
duncanm is on a distinguished road
Default

Lithium cell open-circuit voltages don't tend to drop much (as you've measured) as they discharge.

It probably drooped a whole more when you pressed the button and drew some current.
__________________
TT Outback
Reply With Quote
  #5  
Old 4th February 2017, 11:37 PM
Ratbag's Avatar
Ratbag Ratbag is offline
Administrator
 
Join Date: Jan 2012
Location: Bayside, Melbourne, Vic
Year: MY06, MY10
Model: Forester SG & SH
Transmission: 5MT/DR & 4EAT Sports
Posts: 6,198
Ratbag is on a distinguished road
Default

For certain, Duncan.

Same with all batteries IME. A fairly dead car battery that measures a no load voltage of 12.3V may well drop through the floor when trying to start the car!
Reply With Quote
Reply

Tags
central locking, key battery change, key battery voltage, keyless entry, remote entry system

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -3. The time now is 07:35 PM.


Powered by vBulletin®
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.