I assumed that it was because the rest of the sensors are "reset" and provising accurate info tot he PCM, and the pcm doesn't know to ignre the artificially low temp readign it's getting fromthe trans temp sensor until it runs a bit check and sees that the value is out of range for the rest of the conditions. I don't think it's actually in tow haul, but the shifting does feel noticably different. I noticed the same thing.shifting is much firmer and it holds in each gear much longer both on accel and decel. What the Boman is saying, I think, is it feels like the transmission defaults to tow haul mode if, when the temp sensor has failed you shut off the truck and restart it before the trans has a chance to cool off completely. I, too, use tow/haul when I tow, and think it's great. Will I damage anything by driving the truck tomorrow and Thursday? So.here are the questions- As long as I'm in there, is it worth it to change the harness? Where does it typically short and is it obvious? I assume it's an EMI shielded harness.Is the harness completely contained within the trans? How hard is it to change?.and the two biggies.will my local NAPA or CarQuest have the parts (sensor and harness) or will I have to go to the dealer?.and even if I do get the parts tomorrow, I won't likely be able to get to it until the weekend. All up, that sure looks like trans temp sensor to me. Among others, I got P0710, Trans temperature circuit P0713 Trans Temp Sensor Circuit High (I assume that means a high resistance reading.kinda like an open switch), U1058 Missing or Invalid data (I assume on the instrument panel for the trans temp). When I got home, I hooked up the autoenginuity scanner and pulled codes. Drove about 6 or 7 miles, and when the trans temp gage got just about to where it normally indicates, the trans temp dropped to zero, the check gages light came on, and the tow.haul light started to flash. So, if you find yourself in this predicament, find a safe place to pull off the road and shut the engine off, wait a minute or so and then restart it.OK.a bit more detail.when I started the pig up to leave work, temp gage worked and only the check engine light was on. So, avoid extended driving when the transmission is in fail safe mode.Ī transmission that goes into limp mode will sometimes reset itself when the engine is shut off and restarted. Excessive heat build up in an automatic transmission is the #1 cause of catastrophic failure. Maximum speed while in limp mode is around 30 mph.Ĭontinuing to drive the vehicle with the transmission in fail safe or driving faster than the recommended fail safe speed will cause the transmission to overheat. When the transmission is in fail safe mode, the vehicle should only be drive home or to the repair shop. In fail safe/limp mode, the transmission will have limited functionality and will lock in either 2nd. This can be described as shifting into the wrong gear, skipping the intended gear and shifting back and forth between two gears.Ī failed transmission solenoid or an open circuit anywhere in the electrical system may cause the transmission to go into Fail Safe (or “limp” mode as it is also called) in order to protect the transmission from internal damage that might be caused by the faulty solenoid or open circuit. ![]() A faulty shift solenoid can cause the transmission to downshift uncontrollably (in other words at random times) or not downshift at all, even when coming to a complete stop.Įrratic Shifts: A defective shift solenoid can also cause the transmission to shift erratically. ![]() When the vehicle comes to a complete stop the transmission downshifts into first gear. No Downshift(s): When the shift solenoids are function properly, the transmission automatically downshifts as the vehicle speed slows. ![]() These shift delays can occur when you first shift the transmission into a gear and when the transmission is shifting between gears. During a shift delay no power is delivered to the drive wheels – it’s as if the shifter is in neutral. A faulty shift solenoid can cause delayed shifts of a few seconds or up to one minute or longer. There primary problem symptoms of a faulty shift solenoid are delayed shifts, no downshifts and erratic shifts.ĭelayed Shifts: When the shift solenoids are working properly, shifts occur smoothly and without delay.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |