p2138 engine code

[CTScott]

Originally Posted by crazylegs

I never had to use one of those things before

ok this is what I got so far with the multi meter

when I checked the resistance (turn the dial to the horse shoe looking symbol at 200k) these are the numbers I get.

VPA APP a20-6 (Blue) to ECM a21-55 (blue) = 130
VPA2 APP a20-3 (Yellow) to ECM a21-56 (red) = 130

I tested the rest of the connections from the APP to the ECM and I got the value of 0 for each connection

so with that info I got I really still not sure If it means my wiring is good or bad. as I never done this before.

Also I noticed 2 wires the VCP2 a20-1 (white) and the EPA a20-5 (green) both go into the a different connector just above the pedal. and I do have cruise control is this the throttle control system exhacker1 was talking about. I'll have to go see where the blue and yellow wire go to.

also did a little test to the ECM and got these results which I assume means the ECM is working fine but I don't have a clue.

I checked the voltage by connecting the following pins on the APP connector while the ignition was set to ON.

VCPA (a20-4) and EPA (a20-5) = 5.05v
VCP2(a20-1) and EPA2 (a20-2) = 5.05v

If you have a Rostra cruise control, that would explain the inline connector. If that is the case, that would likely be the culprit.

[crazylegs]

ok I traced the yellow wire to a drive by wire cruise control module and both the VPA wires to this thing. I wonder if this could be the issue assuming that the other info I posted is good. if I unplug the unit the car runs but I have no peddle control just like when I everything goes bad. so I'm starting to think this thing is the issue.

[crazylegs]

yeah it is a rostra cruise control module is that an after market job or do most Yaris's with cruise control have this model?

[CTScott]

Originally Posted by crazylegs

yeah it is a rostra cruise control module is that an after market job or do most Yaris's with cruise control have this model?

It is aftermarket, but Toyota approved aftermarket. Prior to 2009, it was the only dealer installed option for cruise control on a Yaris (even though all Yaris from 2006 on had the functionality built into the ECM). The Rostra cruise control was actually recalled in Canada because of susceptibility to radio transmissions.

[crazylegs]

I just noticed that the rostra wiring was plugged into the original APP a20 connecter so I unplugged it from the rostra wiring and plugged it into the peddle everything seems to work great now. lol damn that was just stupid.

thank you for all your help and suggestions I'm going to drive around now and see how it goes. I think I'm just going to remove all the rostra wiring etc. and maybe do your cruise control DIY when I get a chance. i'll look into that later this year.

[CTScott]

Originally Posted by crazylegs

I just noticed that the rostra wiring was plugged into the original APP a20 connecter so I unplugged it from the rostra wiring and plugged it into the peddle everything seems to work great now. lol damn that was just stupid.

thank you for all your help and suggestions I'm going to drive around now and see how it goes. I think I'm just going to remove all the rostra wiring etc. and maybe do your cruise control DIY when I get a chance. i'll look into that later this year.

Go visit your local dealer and take advantage of the recall. I think they uninstall the rostra and give you a hand full of money (since they do not consider there to be an alternative). Then, You can shoot me less than 1/4 of what they pay you for the Rostra and I'll shoot you the OEM cruise control kit.

[ezhacker1]

aha, it WAS a throttle controller, just of a different type lol. Glad to hear things worked out.

[crazylegs]

Originally Posted by ezhacker1

aha, it WAS a throttle controller, just of a different type lol. Glad to hear things worked out.

Yeah im glad too lol