Rx300 Computer Diagnostis

lexdog · July 8, 2009

So I just got my 02 rx300 back from AAMCO, long story shore vsc+check engine light = replace solenoid D

After they finished the work, lights came back on and they saying they tested the new solenoid its fully working

but the computer is not telling the tranny to shift into 4th gear.... suggested I take it to a dealer and have them do a computer scan.

Anybody know ball park how much a computer scan will cost and if there any DIY remedies to resolve this ???

lenore · July 8, 2009

I doubt that is the problem. Give us a code, but I suspect there is debris in the valve body preventing the piston from moving and hince your lost of fourth gear.....Your tranny may be toast. that solenoid actuates a piston which creates a chain of events for shifting. but if the valve body which has the little pistons is gummed up from metal debris than they wont move. The only other possibility are the tranny speed sensors. Read this post:

http://us.lexusownersclub.com/forums/index...showtopic=57542

mikey00 · July 8, 2009

From your post it sounds like before Aamco worked on your trans, they or someone else read the code and it pointed to a shift solenoid. After replacement the CEL is back on and trans won't shift into OD. Now they are telling you the ECU is not letting the trans shift into OD and to get the code read. This is reasonable for there are some engine related codes that do exactly this. My problem with this whole thing is if they read the first code that pointed to the solenoid, why can't read the code again and tell you what it is?

Bottom line is you need to get the current code read. Maybe even reset it and read it again. You can buy a cheap scanner and do it yourself (Harbor Freight is one of many sources). Also most AutoZones will read it for free. Or find whatever sources are available locally. I would stay away from the dealer at this point unless you are looking for convenience and don't mind spending major $$.

My bet is you are going to have some non-transmission related engine type code that needs to be repaired. Once repaired, the ECU will let the trans shift into OD. But until the current code is read you are shooting in the dark.

lexdog · July 10, 2009

So went to checker auto had the codes pulled today, looks like the same code P0768. malfunction in solenoid D :( :( :(

Wouldn't AAmco or any transmission repair shop have checked the valve body when replacing the solenoid or is the a different area ?

I've taken very good care of the vehicle doing all required maintenance at regular scheduled intervals

mikey00 · July 10, 2009

I think Lenore's post above pretty much nets it out.

I was hoping you were going to come up with one of the engine realted codes where the ECU prevents the tranny from shifting into OD. This is not the case you have a tranny problem. Check here for others that have had the same code and their resolution:

http://www.clublexus.com/forums/search.php?searchid=3974430

lexdog · August 2, 2009

OK so I got the rx300 back from the lexus dealer, the techs there told me they couldn't find any issues with the computer that they thought the issue was a foreign body in the valve body and wanted $500+ to just check the valve body.

Took the Lex back AAMCO were since there the one's who were suppose the check the vale body in the first place, there now telling me they cant find any

problems with the valve body that they did find some small metal fragments in the pan and I want to rebuild my tranny for $3800.00.

Do get I pay another fee at another shop and hav them check the valve body or let aamco do the work. So frustrated here feel like AAMCO is trying to make buck off me cant afford 500+ dollars from the dealer not sure what to do here.

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