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I just picked up a 99 ls400 this afternoon for dirt cheap, just to play around with.
it’s some issues for sure, but one main issue id like to resolve as soon as I can and I’m hoping you guys can help me out.
The car won’t go into reverse. When in reverse it behaves just like neutral.
The car has some codes for speed sensor and shift solenoid. (p0500, p0715, p0770).
I plan on replacing the shift solenoid and the speed sensors but while I have it open I want to make sure the reverse issue gets addressed, or if it needs a new trans entirely, I don’t want to waste time fixing the current one.
What do you guys think is the cause for no reverse?
The car shifts ok other than that, I just drove her home 40 miles on the highway from where I purchased her with no issues.
Nice to find one cheap Rob congrats! Personally I wouldn't consider replacing the transmission if it's shifting fine in all the forward gears these are fairly stout medium duty transmissions unless it's been severely abused or severely neglected but it seems it's shifting fine other than reverse not working.
I've seen a report from a couple of people worked on these in dealerships where they rarely have to replace these transmissions just work involved with the solenoids from time to time but yes probably the answer is in the codes right?
The car won’t go into reverse. When in reverse it behaves just like neutral.
The car shifts ok other than that, I just drove her home 40 miles on the highway from where I purchased her with no issues.
Is the first gear properly selected?
I mean when forward, the car starts skipping the first gear and runs using the second gear and the acceleration is a bit poor?
If so, I have an answer.
Is the first gear properly selected?
I mean when forward, the car starts skipping the first gear and runs using the second gear and the acceleration is a bit poor?
If so, I have an answer.
Thanks guys, yes under $1k... $700 to be precise. I think it’s starting in 1st gear, seems to have good pep off the line but I haven’t driven one of these cars since high school 14 years ago so what do I know.
Also, just to be clear, when in park the car is in park, neutral still acts like neutral, and the forward gears appear to be ok... but again I’ll probably need to double check the car tomorrow about the first gear thing. Anything else, specifically, I should make note of when I go look at it?
From what I’ve read, so far, p0770 doesn’t seem to be related to the reverse gear.
I read about some issue with the temperature affecting reverse but this car won’t go reverse hot or cold so I’m at a bit of a loss.
Can any of you point me in the right direction towards other threads to read or anything that might get me closer to getting reverse back?
Thanks guys, yes under $1k... $700 to be precise. I think it’s starting in 1st gear, seems to have good pep off the line but I haven’t driven one of these cars since high school 14 years ago so what do I know.
From what I’ve read, so far, p0770 doesn’t seem to be related to the reverse gear.
I read about some issue with the temperature affecting reverse but this car won’t go reverse hot or cold so I’m at a bit of a loss.
Can any of you point me in the right direction towards other threads to read or anything that might get me closer to getting reverse back?
Correct, it’s shift solenoid E but from what I can tell so far, that is not related to reverse...
Originally Posted by sndlight
Your shift solenoid E will not prevent your transmission from moving the car forward. It will only prevent the torque converter locking up / lock it up constantly.
Another question I have that maybe you guys know the answer to... I have a friend who will give me a transmission from an 02 sc430 for very cheap... technically it’s the same (a650e) but is it truly the same from car to car? Can I just plug and play swap the sc430 trans into the Ls400?
Thanks guys, yes under $1k... $700 to be precise. I think it’s starting in 1st gear, seems to have good pep off the line but I haven’t driven one of these cars since high school 14 years ago so what do I know.
Also, just to be clear, when in park the car is in park, neutral still acts like neutral, and the forward gears appear to be ok... but again I’ll probably need to double check the car tomorrow about the first gear thing. Anything else, specifically, I should make note of when I go look at it?
From what I’ve read, so far, p0770 doesn’t seem to be related to the reverse gear.
I read about some issue with the temperature affecting reverse but this car won’t go reverse hot or cold so I’m at a bit of a loss.
Can any of you point me in the right direction towards other threads to read or anything that might get me closer to getting reverse back?
Oh man I wish I could find a 99 that won't go into reverse for $700. I bet once the codes are figured out she will sort herself out. She's probably just angry about the codes and won't go into R even if its not officially "related".
I don't think it's a shift solenoid issue. See the solenoid table below.
A650E Shift Solenoid Table
The table indicates that both "R" and "1st" gear needs S1=ON, S2 OFF, S3 OFF and S4 OFF. If these solenoids are not working OK, "1st" will not be selected neither. The problem must not be caused by shift solenoid(S). Then what is causing the only No reverse condition?
I have a few more questions. Does the gear indicator installed in the cluster unit work OK?
Is "R" acting completely the same with "N"? I mean the engine RPM, the audible sound and the vibration just the same or any slight difference is there?
I don't think it's a shift solenoid issue. See the solenoid table below.
A650E Shift Solenoid Table
The table indicates that both "R" and "1st" gear needs S1=ON, S2 OFF, S3 OFF and S4 OFF. If these solenoids are not working OK, "1st" will not be selected neither. The problem must not be caused by shift solenoid(S). Then what is causing the only No reverse condition?
I have a few more questions. Does the gear indicator installed in the cluster unit work OK?
Is "R" acting completely the same with "N"? I mean the engine RPM, the audible sound and the vibration just the same or any slight difference is there?
Yamae, thank you. I have already screenshotted your diagram from the other thread about a similar issue, and I agree with you... this is a different issue.
To answer your question, yes, the gear indicator works OK. There is no difference between “N” and “R”, the rpm does not change, no audible or vibration change that I noticed.
Yamae, thank you. I have already screenshotted your diagram from the other thread about a similar issue, and I agree with you... this is a different issue.
To answer your question, yes, the gear indicator works OK. There is no difference between “N” and “R”, the rpm does not change, no audible or vibration change that I noticed.
You are welcome, CCC-TT. So you have already seen the table and assumed that those solenoids were not related to your problem. Also "R" is just like "N" or "P". The neutral safety switch seems to be OK since the gear indicator works.
When we only think about shift solenoids, the difference between "R" and "N" or "P" is that "S3" is OFF / ON. If "S3" is always ON or stuck mechanically, "R" will be performed like "N" or "P". But in this case, the forward gear will be selected only "4th". You were able to run a freeway and there seems to be no problem on "S3".
Other than those shift solenoids S1-S4, there is a reverse control valve. See below. I don't know this valve is related to your problem or not, this is the only valve named reverse *****.
You are welcome, CCC-TT. So you have already seen the table and assumed that those solenoids were not related to your problem. Also "R" is just like "N" or "P". The neutral safety switch seems to be OK since the gear indicator works.
When we only think about shift solenoids, the difference between "R" and "N" or "P" is that "S3" is OFF / ON. If "S3" is always ON or stuck mechanically, "R" will be performed like "N" or "P". But in this case, the forward gear will be selected only "4th". You were able to run a freeway and there seems to be no problem on "S3".
Other than those shift solenoids S1-S4, there is a reverse control valve. See below. I don't know this valve is related to your problem or not, this is the only valve named reverse *****.
Thank you Yamae, it appears the Reverse Control Valve would be the logical place to start.
From the searching I’ve done, I haven’t come up with much in regards to Lower No.2 Valve Body... I would assume this is deeper in the transmission that the Valve body which houses the shift solenoids?
Also, I was not able to find a part or part number associated with the Reverse Control Valve. Is this a part that can be purchased?
My first guess is that a valve like that is less likely to break than it is to get jammed/gummed up. Depending on location of the No.2 Valve Body Id be inclined to just remove it, clean and reinstall... what are your thoughts?
Thank you Yamae, it appears the Reverse Control Valve would be the logical place to start.
From the searching I’ve done, I haven’t come up with much in regards to Lower No.2 Valve Body... I would assume this is deeper in the transmission that the Valve body which houses the shift solenoids?
Also, I was not able to find a part or part number associated with the Reverse Control Valve. Is this a part that can be purchased?
My first guess is that a valve like that is less likely to break than it is to get jammed/gummed up. Depending on location of the No.2 Valve Body Id be inclined to just remove it, clean and reinstall... what are your thoughts?
These are from a JDM Celsior's parts list and I'll add translations with full p/n.
Translations of related parts and full p/n.
35224 reverse control valve 35224-30010
35224A reverse control valve strait key 35493-30040
35224B reverse control valve plug 90339-05020
35224C reverse control valve spring 90501-06065
I just went to drive the car a bit to get a feel for what is going on again. I also took a quick video... notice the speed sensor is greatly affecting the speedometer and reading like I am driving much faster.
Also, I noticed a slight grab when I move from neutral or park, into reverse... like it attempts to move back ever so slightly, almost unnoticeable but then behaves like neutral... this would also seem to line up with the Reverse Control Valve being bad... I think.
Let me know your thoughts.
(This is a private link that can only be viewed by guys reading this thread)
I just went to drive the car a bit to get a feel for what is going on again. I also took a quick video... notice the speed sensor is greatly affecting the speedometer and reading like I am driving much faster.
Also, I noticed a slight grab when I move from neutral or park, into reverse... like it attempts to move back ever so slightly, almost unnoticeable but then behaves like neutral... this would also seem to line up with the Reverse Control Valve being bad... I think.
Let me know your thoughts.
(This is a private link that can only be viewed by guys reading this thread) https://youtu.be/jYDl3G0TjJ0
Before I comment, could you try lifting the car up some?
At least 2 rear tires should be off the ground and those should turn freely. This helps to check that gears are engaged or not.
Regarding the speed sensor, the speedometer is showing the speed like this way using 4 ABS sensors. The calculation is done there.
07-18-20, 01:02 PM
No reverse.
