code 42 please help baffled
 

hi i have a supra 1993 auto
i had a diagnostics done which came up code 42 on this as the od light blinks all the time when driven or stays lit if i press it.
my car was in a specialist tuning garage that deal with all jap cars
they tested all the sensors (all clear) tried a new ecu unit still code 42 done a few other tests and said i needed a new convertor new speedometer
had a new one fitted still the od light blinks
they have now done another diagnostics level 1 to 10 i think they said and they have come up with a voltage fluctuation on the overdrive and i need a new piece between the gear box and engine torque i think they said
if anyone else has had a similar problem or know anything about this subject then please enlighten me
almost forgot the car drives great and the gear box is really smooth

thanks for any help much appreciated

just remembered they said i probably need a new tool convertor but no guarantees how hard is this code to narrow down

code 42
 

I had this problem on my mk4, along with a faulty cruse,and electric front spoiler, it will also affect the steering but, you may not notice this. The problem was dry soldered joints in the combination meter. (The car speed signal comes from the prop shaft sensor and enters the combination meter where it is "cleaned up" and sent out to other parts which require the car speed).
To fix it, I had to reflow the soldered joints on the combination meter pcb. (the pcb which contains the plug connector).Try another combination meter first, if you can.

Is it an n/a or a tt?

For US-spec, code 42 is "No. 1 Vehicle Speed Sensor Signal"?

Unfortunately I haven't heard of this specific problem before, but I'll ask a couple of friends I have with auto tt's. Please be patient as this may take a few days for me to get in touch with my buddies.

Also, please keep us informed - as I have a 6spd, I haven't had this code before on my mkiv.

my supra
 

mines a 1993 nonturbo auto
they told me code 42 is a speed sensor problem
most of the time if i put my foot down for speed the od light blinks also when i put my foot down for quick speed fast acceleration the red triangle light appears all lights are back to normal when restarted sometimes i can drive 10-15 miles no lights?
but car carries on driving as normal whether lights blink or not
ive had the auto box looked at and they said it doing what it should be doing no probs there
they said all speed sensors have been checked speed convertor mph-kmph been changed they told me i need a torque convetor due to there being voltage fluctuation in the higher gears where as it should be steady
the gear box place told me the car has a variable solenoid so there will be a voltage surge due to the lockout i think they said well confused
im thinking theyve missed something stupid dont know who knows whats best
any new info would be much appreciated

code 42
 

Hi again, did you change the combination meter? like I said last time,it is also known as the odometer or mileometer. It is in the the middle of dash,it also displays ignition,cruise etc
When they said it may be the convertor do they mean a kilometer to mph convertor,ie: has the car been changed over from kilometers to mph?.If it has this convertor unit may be faulty.

supra
 

hi they fitted a new convertor kmph to mph and they fitted a new speedo at the same time i had this done by supra specialists cost me ?350 at the time of diagnostics they assured me it was convertor but it made no difference and they never managed to sort out the code just said definatley not electrical due to elimination probably torque convertor which would cost another 400

code 42
 

hi why did they change the speedo if it was working? If the combination meter has not been changed, then this should be changed next.
The the trip and mileometer may be working ok, but the speed signal leaving the unit may be missing. This (cleaned up) speed signal leaving the the combination unit is used by gearbox.
This was the cause with my mk4.

Here's the advice a friend of mine gave, who owns an mkiv tt auto:

Just my guess would be “Cel” may be having a cold weather issue, or needs to re-solder the connections – I sure wouldn’t replace anything major until I was sure it was really a mechanical (vs. signal) malfunction...