1990 LS400 Traction Control Issue
#17
I'm a litle confused here,at the start of the thread you had a traction control system fault and now you have moved onto O2 sensors.
When you read the codes did you perform an engine code pull or Trac code pull?
The reason I ask is because the most common cause of the TRAC light coming on is when the trac accumulator pressure is too low and the pump stays on too long in an effort to bring the pressure up.
This normally gives fault code 19 when in trac diagnostic mode.
If there was no indication of faulty O2 sensors before you replaced them it could be that you have misread the codes and from there replaced the O2 sensors with incompatible generic replacements.
I would start by refitting the original O2 sensors and then see the result and proceed from there.
When you read the codes did you perform an engine code pull or Trac code pull?
The reason I ask is because the most common cause of the TRAC light coming on is when the trac accumulator pressure is too low and the pump stays on too long in an effort to bring the pressure up.
This normally gives fault code 19 when in trac diagnostic mode.
If there was no indication of faulty O2 sensors before you replaced them it could be that you have misread the codes and from there replaced the O2 sensors with incompatible generic replacements.
I would start by refitting the original O2 sensors and then see the result and proceed from there.
#19
Actually, after reading numerous threads here and doing other research, I discovered that when the Check Engine light comes on with the 90 LS400, the Traction Control is turned off. I did not have any Traction Control codes and it wasn't blinking, it just went to "TRAC OFF" whenever the CEL would come on.
Yes, I did pull codes, and no I did not misread them. I got codes 25 and 26 (if I remember correctly, it's been a while). That seemed to point in the direction of the O2 sensors, again based on research of potential faults. So...what I thought was a Traction Control problem no longer seemed like an issue with the Traction Control, it was another issue, as I was not previously aware that the TRAC OFF light would show when the CEL light was showing. I got 2 new O2 sensors and switched them out. I then pulled the fuse and reset the ECM to clear the codes. The codes never returned and the car is running fine now.
Yes, I did pull codes, and no I did not misread them. I got codes 25 and 26 (if I remember correctly, it's been a while). That seemed to point in the direction of the O2 sensors, again based on research of potential faults. So...what I thought was a Traction Control problem no longer seemed like an issue with the Traction Control, it was another issue, as I was not previously aware that the TRAC OFF light would show when the CEL light was showing. I got 2 new O2 sensors and switched them out. I then pulled the fuse and reset the ECM to clear the codes. The codes never returned and the car is running fine now.
#20
To answer your question, I did pull the engine codes, not specifically traction control codes. I did this by using the jumper method on LexLS.com. The only light blinking during this process was the CEL light, nothing else.
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Stuno1
IS F (2008-2014)
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09-05-14 06:57 PM