5-speed A750 trans won't shift in to 5th gear. (2 Viewers)
- Thread starter MongooseGA
- Start date
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They sure do! I'll do some digging when I get home. Solenoid 'E' is indeed the same as the SR solenoid that I was talking about, so even a blind squirrel finds a nut occasionally I guess...
- Thread starter
- #63
Also finding stories of bad harnesses/ connectors. I found the OEM transmission harness (P# 82125-60383). I'll order one of those as well if it comes to it.
Pffft. You've got, what, 48 hours till you need to leave for COTR? That's plenty of time to tear apart a transmission, wiring, and associated bits and bobs!
Pretty sure I posted this before, but this is all the diagnostic manual has for P0771. Of note, an issue in the wiring *should* throw a different code (P0985, P0985 as posted previously).
Didn't get a chance to post here before, but I'd say you're finally on the right path. Techstream is pretty much required for the more involved troubleshooting.
A word of caution against the parts cannon approach: It will get you a lot of new parts but not necessarily solve the issue at hand.
Also, hopefully the C12** codes don't come back but they could mean a failing booster motor (which would be unrelated to the transmission issue.)
A word of caution against the parts cannon approach: It will get you a lot of new parts but not necessarily solve the issue at hand.
Also, hopefully the C12** codes don't come back but they could mean a failing booster motor (which would be unrelated to the transmission issue.)
- Thread starter
- #67
I actually agree on the parts cannon. At this time I'm happy to buy anything that is reasonably inexpensive, but would probably insist on more diag before looking at more expensive parts.
Yeah, the brake codes weren't great to see. I haven't been given any indication the system is set to go yet, but it is on my radar already and I've discussed it with Patch as well.
Keeping in vain of spending your money
consider buying a brake booster at nearly 31% off at Genuine Toyota Parts and Accessories: Official Online Store Serra Toyota of Decatur - https://autoparts.toyotaofdecatur.com/
I'd probably run a brake booster time test (looking for sub 40 seconds) first myself, but, it's not like they're going to get any cheaper...Keeping in vain of spending your money
consider buying a brake booster at nearly 31% off at Genuine Toyota Parts and Accessories: Official Online Store Serra Toyota of Decatur - https://autoparts.toyotaofdecatur.com/
- Thread starter
- #70
Keeping in vain of spending your money
consider buying a brake booster at nearly 31% off at Genuine Toyota Parts and Accessories: Official Online Store Serra Toyota of Decatur - https://autoparts.toyotaofdecatur.com/
You've always been so good at helping me spend money
Eyedaho
SILVER Star
It sounds like the diagnostics aren't pointing to a wiring issue, but I think the top connector is susceptible to damage if the motor/trans is jacked up for things like changing steering racks, motor mounts, etc.
- Thread starter
- #72
Could be. Last it was lifted (if it was lifted, i don't recall offhand) would have been when I did my steering rack bushings earlier this year. Prior to that, I did engine mounts maybe a year or two ago.
This is well outside of my diag level. I'm usually OK with mechanical diagnostic, electrical is Greek to me.
2001LC
SILVER Star
ABS DTCs:
Can be from most anything. Even a low or bad battery. If master grades well, I'd not worry to much about it. But the sale price on today, is hard to pass up if even just for a spare!
forum.ih8mud.com
If you or your shops, can't find and correct AT issue. Ship it to me in Denver. I will fix it!
Can be from most anything. Even a low or bad battery. If master grades well, I'd not worry to much about it. But the sale price on today, is hard to pass up if even just for a spare!
Brakes ...... Overdue write-up.
First and foremost: Brakes should only be worked by those, with high level of mechanical abilities and experienced with brake systems. With the age of all 100 series today, in our aging fleet. Any issue, with brake master assembly. IMHO, best and safest course of action. Have the whole brake...
forum.ih8mud.com
If you or your shops, can't find and correct AT issue. Ship it to me in Denver. I will fix it!
- Thread starter
- #74
ABS DTCs:
Can be from most anything. Even a low or bad battery. If master grades well, I'd not worry to much about it. But the sale price on today, is hard to pass up if even just for a spare!
Brakes ...... Overdue write-up.
First and foremost: Brakes should only be worked by those, with high level of mechanical abilities and experienced with brake systems. With the age of all 100 series today, in our aging fleet. Any issue, with brake master assembly. IMHO, best and safest course of action. Have the whole brake...
If you or your shops, can't find and correct AT issue. Ship it to me in Denver. I will fix it!
Very good point on the low battery for those codes. In fact, I did need to put a jump box on it to get it started the first time. Since the codes did not reappear, that may have been what happened. Although, having the ABS/VSC/TRAC lights on when the trans issue started is eyebrow raising.
I am not opposed to taking you up on your offer! Let me exhaust what I can myself and maybe we can revisit. Oh man, you'd pick my truck apart
2001LC
SILVER Star
ABS will shut down, when most any DTC comes up. Toyota doesn't like ABS working, when we've most any engine or transmission issues. ABS unit (black box on side of master) is the VSC/TRAC active component. It's also has a CPU (by brake pedal), that is connected to many sensors, in one way or another. So the AT issues, was very likely throwing a DTC the kick on the ABS lights. Also the low battery needing a jump, result in low or no booster motor speed/low pressure. Clear and watch for recurrence is always advisable. Also read up on clues, of good or bad brake master in the link I provided.
Be a good Idea to post screenshots of engine date.
You can also have a buddy ride along, and run the tech stream record function. I'd do this from cold start up drive, to full operating temp. Taking AT through all gears and condition (acceleration, cruising and engine braking) also. Recorder, auto shuts off every few minutes, is why you need a helper to hit record button again and again. This give live continuous date. See OM or FSM, at what point we shift to 5th (OD). Like what AT fluid/engine temp minimums, along with certain MPH/RPM. See what is going on at those point and beyond.
I do "pick them apart". I'd be willing to bet, I find and correct more on 100 series, than most anyone in the world. According to Toyota parts department manager. I order more small and unusually parts, then anyone over the past 25 years has. But even after all these years working on only 100 series (well' a few 200 series). I still find and work on stuff, for the first time. We've a lot of systems!
Be a good Idea to post screenshots of engine date.
You can also have a buddy ride along, and run the tech stream record function. I'd do this from cold start up drive, to full operating temp. Taking AT through all gears and condition (acceleration, cruising and engine braking) also. Recorder, auto shuts off every few minutes, is why you need a helper to hit record button again and again. This give live continuous date. See OM or FSM, at what point we shift to 5th (OD). Like what AT fluid/engine temp minimums, along with certain MPH/RPM. See what is going on at those point and beyond.
I do "pick them apart". I'd be willing to bet, I find and correct more on 100 series, than most anyone in the world. According to Toyota parts department manager. I order more small and unusually parts, then anyone over the past 25 years has. But even after all these years working on only 100 series (well' a few 200 series). I still find and work on stuff, for the first time. We've a lot of systems!
- Thread starter
- #76
Update from the trans shop:
Solenoids all tested perfectly against Toyota's standards. So, we can rule that out and probably anything inside the trans.
He just mentioned to me that he noticed some coolant drippage on the trans wiring harness connector at the top of the trans. Disconnected, cleaned it up some, buy no improvement. I found this interesting though, as there is a thread here where another guy had damage to that same connector, and replacing the wiring harness was the fix for his issues.
Well, the new wiring harness arrives tomorrow. He'll put it in while the truck is on the lift and we'll see if any improvement. If not, I'm bringing the truck home so continue working on it.
Solenoids all tested perfectly against Toyota's standards. So, we can rule that out and probably anything inside the trans.
He just mentioned to me that he noticed some coolant drippage on the trans wiring harness connector at the top of the trans. Disconnected, cleaned it up some, buy no improvement. I found this interesting though, as there is a thread here where another guy had damage to that same connector, and replacing the wiring harness was the fix for his issues.
Well, the new wiring harness arrives tomorrow. He'll put it in while the truck is on the lift and we'll see if any improvement. If not, I'm bringing the truck home so continue working on it.
- Thread starter
- #77
Picked her up today from the trans shop. The shop refused to charge me for anything, including fluids and gaskets. Truly, they were a pleasure to work with and I will likely bring the Ms' El Camino to them to have that transmission replaced with a better one. I ended up buying him a bottle of bourbon to say thanks. If you're in the Metro Atlanta area, Speedy Transmissions in Marietta. Scott, the owner, is really a top notch guy.
Unfortunately I ordered the internal wiring harness, not the external one I'd intended to. I'm going to install this relay control module and see if the harness is still necessary.
The module I'm replacing is circled in the diagram below. I pulled the glove box and this module isn't immediately obvious. Any chance one of y'all knows where this thing lives?
Unfortunately I ordered the internal wiring harness, not the external one I'd intended to. I'm going to install this relay control module and see if the harness is still necessary.
The module I'm replacing is circled in the diagram below. I pulled the glove box and this module isn't immediately obvious. Any chance one of y'all knows where this thing lives?
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Well that was good news and bad news at the same time. I'm sure they are a lot of others like me that are following this thread. Hope you get overdrive back soon. So now you have an extra transmission eh?
- Thread starter
- #79
I sure do!
Classy move by both of you guys!
