natec76@mail.ur

I have a 93 Maxima GXE and have recently had tranny work done. The problem is that when the car is in overdrive on the highway and you come to a hill it gets stuck between overdrive and the lower gear. AKA it doesn't downshift and you lose speed as the RPM's just rise like its in neutral. However if the over drive is off or manually disengaged it is fine. Does anyone know what might be wrong with the car?

subs1000w

sounds like the overdrive clutches are toast

time for a rebiuld

Wiking

Not so fast. Only after KNOWING the solenoids do get their share of the common juice of +12V...

I think its time for cleaning TCU & ECU connectors.

lukiluki: http://www.cardomain.com/memberpage/748507/14

lukiluki: http://www.cardomain.com/memberpage/748507/15





.

ntjoe

Another thing to check is to run the car about 45mph or so with O/D off, then stomp the pedal and see what happens. If it downshifts and takes off, it might just be a solonoid. If it slips, then it is more than likely the clutches in the tranny.

My 93 GXE did the SAME thing you list, and would slip if I stomped it as listed above. I drove it like that for a year before I sold it, just taking it out of O/d on hills and such. Did fine once you got in the rythmn of it.

Good luck, Joe

Wiking

I suppose similar autotranny selftest is found at www.autozone.com


Testing

how to run the self-diagnostics test on your auto tranny:

1. Start engine and warm it up to normal engine operating temperature.
2. Turn ign switch to "OFF"
3. Set A/T mode switch to "AUTO"
4. Set O/D switch to "ON"
5. Move selector lever to "P" position
6. Turn ign switch "ON" (do not start engine)
7. Power indicator lamp should come on for about 2 seconds
Then:

1. Move selector lever to "D" while depressing brake pedal
2. Turn ign switch "OFF"
3. Set O/D switch to "OFF"
4. Turn ign switch to "ON" (do not start engine)
5. Move selector lever to "2" position
6. Set O/D switch to "ON"
7. Move selector lever to "1"
8. Set O/D switch to "OFF"
9. Depress accelerator pedal fully and release it
10. Check power indicator lamp

Codes:
There should be a longer start signal followed by 10 shorter signals, note which of the 10 short signals is longest
All flickers the same: self-diag OK
1st flicker is longer than others: revolution sensor circuit
2nd flicker is longer: vehicle speed sensor sensor circuit
3rd flicker is longer: throttle position sensor circuit
4th flicker is longer: shift solenoid valve A circuit
5th flicker is longer: shift solenoid valve B circuit
6th flicker is longer: timing solenoid valve circuit for non limited slip tranny(89-94GXE); overrun clutch solenoid valve circuit for limited slip tranny (some, maybe all auto 92-94SE)
7th flicker is longer: torque converter clutch solenoid valve circuit
8th flicker is longer: fluid temperature sensor and A/T control unit power source circuit
9th flicker is longer: engine speed signal circuit
10th flicker is longer: line pressure solenoid valve circuit
lamp does not come on: inhibitor switch, overdrive switch, and throttle position switch circuit

------

Solenoids

The solenoid resistances may be measured, on the tranny side, connector opened:
Its got eight pins, numbered the same as in TCU connector.

Tranny side connector pins from left to right, top row first:
1 | 6 | 8 | 7
5 | W | W |none

Resistances measured to ground:
Line pressure. 1 to gnd = 2.5 -5 ohms
Torque converter. 5 to gnd = 10 -20 ohms
Shift solenoid valve A. 6 to gnd = 20 -40 ohms
Shift solenoid valve B. 7 to gnd = 20 -40 ohms
Timing 8 to gnd = 20 -40 ohms
Fluid Temp. W measured against W = 2.5K Ohms Cold