Hello!

I have a question regarding a check engine code that I keep reseting and that keep appearing again, while nobody can find anything with the car.

I have a 1996 Camry (V6, LE). Recently the check engine light appear. I went to a shop and they pulled the code DTC P1705 from the ECU, which is related to the transmission. They checked the transmission and the Direct Clutch Speed Sensor but couldn't find anything wrong. So we reset the code but it came back shortly after (after 2 hours of driving).
Being no specialists of transmission issues, they gave me the address of a transmission shop. Same diagnostic: nothing wrong with the transmission or the sensor, both tested good. The check engine light appeared again recently and I don't know what to think about it. Could it be a loose wire, or is there an ongoing condition that the shops could not see?
If anyone had this issue before, I will for sure appreciate to hear about your experience! I love this car!

Thanks!

Vic

 

I've had the same problem, my mechanic replaced the speed sensor, it still wasn't working and the light came on, and the transmission shifted sluggishly at slower speeds, the mechanic replaced it two more times thinking it was a faulty speed sensor, and reset the check engine light, but after I picked it up today from the shop the light came on the first time the transmission shifted at low speeds. My mechanic is very discouraged, and so am I, I don't really want to bring it back to him. Anybody else ever have this problem, and how was it resolved?

 

Year of car and engine type?

 

Me too, P1705, 2000 Avalon.

This has been discussed (as you may have discovered) for more than a decade now as a "sticky" problem (often intermittent). Just investigating it myself now, and no attempt to fix yet, but one thing that everyone may be overlooking, even the service techs, is that there are more than one criteria for this code to NOT pop up.

From another forum, apparently from a Toyota service manual:

______

Direct Clutch Speed Sensor

It's the sensor that sits directly on top of the transmission case.. Easy fix.
This sensor detects the rotation speed of the direct clutch drum.
By comparing the direct clutch speed signal with the vehicle
speed sensor signal, the ECM detects the shift timing of the
gears and appropriately controls the engine torque and hydraulic
pressure in response to various conditions, thus performing
smooth gear shifting.

DTC No. DTC Detecting Condition Trouble Area

P1705

The ECM detects conditions (a), (b), (c), (d), (e) and (f) continuity
for 4 secs. or more.

(2−trip detection logic)

(a) Vehicle speed : 32 km/h (20 mph) or more
(b) 3rd or 4th gear
(c) NC2 < 300 rpm
(d) Park/neutral position switch: OFF
(e) Solenoid valves and vehicle speed sensor are normal
(f) L position: OFF

 Open or short in direct clutch speed sensor circuit

 Direct clutch speed sensor

 ECM

WIRING DIAGRAM
DI02P−03

Direct Clutch Speed Sensor part # 89413-08020 $130.24 RETAIL. [others note where to get cheaper]

______

It looks like Toyota says the (likely?) problem is 

Open or short in direct clutch speed sensor circuit

Direct clutch speed sensor

ECM

BUT, look at the other conditions that are a part of the check, particularly which gear the transmission has shifted to and the park/neutral position switch reading.

My GUESS at this point (no work on it yet) is that sometimes it's something ELSE, such as old transmission oil that prevents correct shifting time (so not in right gear when tested), OR an intermittent (or not) problem in the park/neutral (gear shift) position sensor.

So IF, when I dive into it, the usual doesn't work (testing clutch speed sensor or replacing, etc.) I'll then look for a problem with the gear shift position sensor, and I'd change my Xmission oil too (been intending to do so anyway ... it's 122,000 mi.) to help make sure the shifting times are right. Then there are those "solenoid valves" AND "vehicle speed sensor" to investigate too.

At this point justhinkin is jusguessin, but maybe this will set another direction to this vexing problem?

GLTA!