1993 FZJ80 A442F issue, won't start moving in 1st, but rather 2nd (1 Viewer)

[Drilldeeper]

Hey everyone.
I have posted this on FB 80 group and also searched here.
My truck started to refuse to start moving in 1st gear but in 2nd (or 3rd, not sure) when in D. When I put it in L it will start in that first gear, or even if I'm moving in D, then shift to L, it will find that 1st gear. It also threw 62 code.
Three years ago it was shifting erratically and it ended up being two bad capacitors on the transmission ECU, fixed them and it was shifting fine.
What I've done so far is I checked and installed new capacitors again on the ECU (they're like 60 cents each and a little soldering),
I have also replaced all four solenoids in the transmission and put new fluid.
Same results. Won't start moving in first but will do so in L.
I know the plug by the starter may be the issue. Anything else you can think of?
Thanks!
1993 FJZ80

 

[Malleus]

It's one of the three root causes you've listed;
1» TCU
2» Park/Neutral switch
3» shift solenoid/circuit (I'm betting it's this one)

 

[Malleus]

Download the 1993 or 1994 service manual from the Resources forum, 80 series section (I can't remember if there's a '93 version in there or not, they are both the same for this section) and refer to the Automatic transmission section of the manual.

 

[Malleus]

Hey everyone.
I have posted this on FB 80 group and also searched here.
My truck started to refuse to start moving in 1st gear but in 2nd (or 3rd, not sure) when in D. When I put it in L it will start in that first gear, or even if I'm moving in D, then shift to L, it will find that 1st gear. It also threw 62 code.
Three years ago it was shifting erratically and it ended up being two bad capacitors on the transmission ECU, fixed them and it was shifting fine.
What I've done so far is I checked and installed new capacitors again on the ECU (they're like 60 cents each and a little soldering),
I have also replaced all four solenoids in the transmission and put new fluid.
Same results. Won't start moving in first but will do so in L.
I know the plug by the starter may be the issue. Anything else you can think of?
Thanks!
1993 FJZ80

BTW, who fixed your TCU for you?

 

[voodu3]

Agree with @Malleus try the manual shifting test from the FSM

 

[Malleus]

I'm betting it's wiring, because he can get 1st, just not when he wants it...and his solenoids are newish.

 

[ThreeEyedBandit]

Does the dash show what gear the shifter is in?

 

[Kabanstva]

Agree with @Malleus try the manual shifting test from the FSM

Where are you finding PDF files of the 94 FSM? Thank you for posting this.

 

[Drilldeeper]

BTW, who fixed your TCU for you?

I did three years ago after one of FB group members pointed out it could be the issue.

 

[Drilldeeper]

Does the dash show what gear the shifter is in?

yes it does

 

[Drilldeeper]

Agree with @Malleus try the manual shifting test from the FSM

Thanks, this helps! I'll start checking voltages and stuff before throwing more money at it!

 

[ThreeEyedBandit]

yes it does

Start tracking continuity from the TCM to the trans body(for the solenoids). Your probably on the right track with the connectors next to the starter.

 

[voodu3]

Where are you finding PDF files of the 94 FSM? Thank you for posting this.

Pm me your email and I’ll send the zip file I have of the 94 FSM. Its one I got before we had the awesome resource section on here. Thanks to @Malleus

 

[Drilldeeper]

Just checked the resistance on the solenoid 1 from the TCM connector. It's there but very low, around 1 or 2. Solenoids are new (looks like I didn't need to change them).

 

[Malleus]

1 or 2 what? Gigawatts? Ohms? KOhms?

 

[Malleus]

Where are you finding PDF files of the 94 FSM? Thank you for posting this.

You won't see this on your phone (another good reason to use a computer for computer stuff...)

 

[Malleus]

Pm me your email and I’ll send the zip file I have of the 94 FSM. Its one I got before we had the awesome resource section on here. Thanks to @Malleus

The version in the Resources forum is bookmarked

 

[Drilldeeper]

1 or 2 what? Gigawatts? Ohms? KOhms?

lol good point, I'm getting continuity and about 1 ohm. The manual says normal value is 11-150. Or am I doing something wrong? I check the other solenoid and it read 40 or around there

 

[Drilldeeper]

Start tracking continuity from the TCM to the trans body(for the solenoids). Your probably on the right track with the connectors next to the starter.

I hate that connector, it buggered up my hands last time (three years ago) when I checked it and cleaned it and applied electric grease

 

[Malleus]

lol good point, I'm getting continuity and about 1 ohm. The manual says normal value is 11-150. Or am I doing something wrong? I check the other solenoid and it read 40 or around there

You're probably not doing anything wrong, but your wire is doing you wrong. You should have consistent resistance across the entire shift solenoid circuit. Where are the endpoints you're measuring from/to? Try at the TCU also. You should the same-ish there.

I think that pigtail is still available. If not, you'll have to make one.