SOLVED: TPS SENSOR CABLE WAS NOT CONNECTED

As I posted on another thread, I cleaned up my PCV system. To be able to do this I removed the battery, and after reconnecting it the transmission is in limp mode and the yellow arrow of death (YAOD) is blinking on my instrument cluster.

I will have to use a handmade scanner to read the codes, because I have gone to three indy shops to get my codes read (for another problem) and none can read them even in OBD2 mode. I used to have my own OBD2 reader which I purchased from www.obd-2.com. It would clear the CEL and the service light, but it was not able to read codes so I had to return it. Apparently my car is not totally compatible with OBD2, since this same scanner works fine for US Volvos. I do not want to go to a Volvo dealer for reasons I have previously posted.

The tranny was fine before removing the battery. Sports, econ and winter mode were working fine. The lambda light has been on for the last year, but I have ignored it due to the lack of time and a working scanner. I doubt the fluid level has dropped while the car had no battery. I am betting this is an electrical problem. As another user suggested, I will check in the battery area for a disconnected plug. Any other ideas? Could I have inverted any connectors that would affect the tranny?

 

I test drove the car for about 2 miles and, as expected due to limp mode, if I take it above 4000-5000 rpms it will go into fourth gear. The tranny was working normally without any slipping or strange noises. The lights on the winter/sport switch were also blinking IAW the YAOD.

 

Axel,

See attached pic, there also seems to be different design version but I forgot where I saw it. Not sure which pin is for the tranny ECU but I believe you should be able to find one on-line.

I hope this helps.


JPN

[IMG]local://upfiles/6892/53D79464DBA146E280AB04238C455A83.jpg[/IMG]

 

I don´t think the tranny module is connected to the OBD2 port directly so I can use the blinking lights method. I have to double check the wiring schematics which I don´t have here with me right now, but I am pretty sure that some of the test leads that were available on the OBD1 port are missing on OBD2. A scanner could pick up the codes, but it would have to be a VST. Damn, I´ll have to get raped at the stealership

 

The schematics show that the AW 50-42 Transmission Control Unit is located in the front left area of the engine compartment, in the same area where I was working on Saturday/Sunday. The TCU is connected to the ECU via the wiring harness. If the TCU is disconnected from the wiring harness due to my clumbsiness, it would definitely flash the YAOD and the car would behave like mine is. Now it´s just a matter of finding that darn connector...

 

Maybe you found your problem, hopefully...I'll post back when I find that thread. Good luck w\your troubleshooting

 

Tech, am I making any sense here? Where is the connection between the TCU and the harness? I can´t seem to find any connector in that area.

 

Tranny fluid level, color and smell is OK. P R N D 3 L 3 D N R P R N D 3 L with ten seconds in each gear. The dipstick shows the correct level on the HOT side.

 

OK, problem solved; Electronic.

.....[8D]

But wait, did you drive the car for 15 minutes or longer?


JPN

 

Yes, I drove it for about half an hour before checking the fluid level.

 

I was looking in the incorrect place. The TCU is in the ECU box close to the wiper reservoir. They are connected via a local connector, looks like a bus backplane with about thrity pins. The wiring diagrams apparently meant "left" as in "looking from outside the car", not from the drivers position like they usually do.

The car is not idling correctly either. I can feel the intake hose collapsing when I accelerate sharply too. I am getting very frustrated.

 

Regarding the idling, if I pull the connector on the MAF, it runs rich at 1000 rpms. But at least it doesn´t die doing 400 rpms. The car is hunting for the correct idle point apparently. That should go away after several drive cycles, right?

 

My bet is that there is a vacuum loss somewhere in the intake circuit, but I just can't find it.

I will be travelling on business for the next three weeks. I hate to leave the car in such bad conditions. [:@]

 

Did you read codes from the OBDI?
Maybe the computer just had a brain fart?
Once cleared see how fast they come back.
Most tans codes even the simplest codes will go into limp home mode.

 

The computer had a brain diarreah, rather than just a fart. How can a flashing arrow appear because the battery was disconnected? %^&%^&*(**&^%$#@%^&* to the Volvo gods.

 

BTW, smoke still comes out of the dipstick if I pull it while I am revving. However, it does not come out the exhaust as bad as it did in the past.

 

A connection leading to the trans or the computer might be dirty and a spark might have jumped while connecting.
Or maybe you turned the key on after installing the battery before hooking up the TPS?
That would set a code in the TCM as well.

If it doesn't happen at idle I wouldn't worry to much about it.
You made sure all teh small hoses were clean and free as well?

 

I removed all the hoses that I had access to without taking out the injectors and intake manifold. They were all cleaned thoroughly and checked for obstruction.

I only turned the key after hooking everything up.

Archs are almost always there when you connect the negative. Capacitors should take care of them.

I will quaruple check everything tomorrow when it stops raining. I will also try to build the scanner tomorrow with some leftovers from previous electronic projects.

As always, thanks Tech for your help.

 

No problem.

 

I used a broken remote control from one of my kids remote controlled cars to make a DTC reader and it worked. I was not able to clear the codes though. I tried abouttwenty times.

The 12 V tension blew the LED (I did not have a resistor, stupid me) so I used an analog multimeter in VDC scale to read the pulses.

The codes are:
4 1 1 TPS sensor outside signal range
1 2 1 MAF sensor signal absent
5 3 5 turbo regulator valve fault
2 4 5 idle air control closing signal absent or faulty
2 2 3 idle air control valve opening signal absent or faulty
2 2 5 air conditioning pressure sensor signal absent or faulty

I can't seem to clear them. I understand I have to keep reading until the codes repeat themselves and then keep the switch pressed twice for 6 seconds and that should clear the codes. Is that correct?

How are these DTCs sorted cronologically? Is 4 1 1 the newest code and 2 2 5 the oldest one? That would make sense because in March I pulled the connector on the A/C low pressure sensor to test it.

Another question? There is a calibration screw that regulated the tension on the throttle cable? What is the correct setting? If this is not correctly set would it trigger a 4 1 1?