Toyota FJ Cruiser Forum banner

1 - 8 of 8 Posts

·
Registered
Joined
·
11 Posts
Discussion Starter #1
Hey Cruisers.

‘13 TT, 70k mi, 2nd owner. Far as I know this thing has been a blacktop queen. I take it out on logging roads, snow etc.

But I have never needed the locking diff.

I just had it out on the beach, and I chose to exercise the locker. Got a solid red, (nice choice Toyota, and way to make it clear in the manual. Not.) Drove a little, slow, the solid red worries me so I disengaged. All good.

The next day I’m back on the beach, go to repeat, and the diff won’t lock, the CEL comes on, the TRAC light comes on, and later on blacktop the cruise control is inoperable.

The truck continues to otherwise run perfectly.

This smelled of a software hiccup so I yanked the negative at the battery for an hour.

And it worked! Have not tested the locker as am on blacktop.

So. What’s up?
 

·
Premium Member
Joined
·
11,788 Posts
What 4 wheel drive mode were you in when engaging the locker?
 

·
Registered
Joined
·
3,265 Posts
There may not be any direct connection between use of the locker and the "anomalies" you noted.

When the rear diff is locked, the following functions are disabled:
ABS
Brake Assist
VSC
TRAC

Are you absolutely SURE the other light you saw was the CEL?

To get the diff to lock, you very frequently need to execute a series of shallow left/right turns to get some speed differential between the axles and allow the locking mechanism to engage. Trying to engage the diff lock while stopped, or driving in a straight line, usually won't work.

Disconnecting the battery for a minute or two will delete error codes stored in the ECU, but will of course not "fix" any underlying hardware problems.

I'm not sure that there is any lack of clarity in the Owner's Manual describing locker functions. There are three states:
a) Diff lock disengaged - diff lock light off;
b) Diff commanded to lock, but not yet mechanically engaged - diff lock light flashing;
c) Diff lock engaged - diff lock light on solid

I think the red "warning" color of the diff locked indicator may be appropriate given the handling quirks that may appear when the diff is locked. (Ever been on an off-camber, icy, paved hill with the diff locked and BOTH rear tires start slipping simultaneously?)

If there were any real ECU firmware problems related to locker function, I'm pretty sure they would have been uncovered by now.
 

·
Registered
Joined
·
11 Posts
Discussion Starter #7
Had an icy driveway today, a bit of it steep,
locked the diff, gave the wheel a wiggle, went up backwards, zero issues.

Back to the beach!
 
1 - 8 of 8 Posts
Top