dlouis7

i got one email me dlouis7@hotmail.com

well, i found the problem. no signal from the ecu terminal #24 it is the terminal that sends 12v to the main sfi relay when the key is turned to the on position. the main relay then closes and allows current to flow to the B+ terminals on the ecu, which in turn powers up everything else. i am going to take the computer back to the rebuilders because the lexus tech that i have been talking to says that it could still be the comp and that he has had to send back a few comps because they were not perfect. just to check everything out i jumped the relay terminals and the car started, and the check engine light is functioning. i drove it for about an hour. the comp. rebuilder really did fix the transmission circuts it feels like a different car. all the shift points are back, and overdrive really kicks in.

thanks jzz30 that is what i was making a reference to in my last post (b+ to FP). i tried it and i have found a problem. i have no power in the circuts that power the ecu. i pulled out the trusty repair manual, which by the way is a real lifesaver. those of you out there that do your own work, or try, you have to have one. the tech told me yesterday that i could bypass the pump at the diagnostic terminal under the hood and while i was at it i should check the B+ terminal he said that if i did not have power there the problem was in my harness. the B+ line powers the ecu and the fuel pump ecu. it is run by a main SFI relay i checked the relay and it is good. i just got up and i am preparing to go work on the wire harness. i am not looking forward to it but it is worth 100.00 an hour. i WILL find the cause of the problem today, i have to it is my last day off

well i got the computer back this morning, installed it and......... NO SPARK. i almost fainted. i do not know what is wrong. i also have no fuel but i pulled the pump and ohm checked it and checked it on a 12 volt source, it is good. i also have no check engine light i changed the bulb and still nothing. i have checked all the fuses in the car. under the hood and at the drvs kick panel. i called the local lexus dealership and spoke to a tech, he told me to check the fuel pump ecu i will check that and also B+ to FP at the diagnostic terminal. if this doesnt work i will have to take it in, and at 100.00 an hour it will not be pretty. the problem i am having is, spark is pretty simple if you know which components are involved. from the wiring schem. in the repair manual it would seem that the only components are the coil-igniter-ecu-ignition switch, and they are all good. does anyone know if there is another sensor that the ecu would read in order to signal the igniter. 93 sc300

well, yesterday i took my computer to a ecu repair facility. The facility advertises on ebay, and lucky for me i live in the general area. when i took it in i had already opened it and did not see any appearant burns. The tech Dave was really cool and he showed me a ton of burns (the solder around a few circuts were not black as i expected to see, Dave explained that when the circuts burned, the way to tell was that the solder was no longer shiny chrome, but was a dull silver because of the acid from the circut). he explained that the number 38 computer was one of his best selling rebuilds. he was even able to look at it and tell me that i was having some minor shifting problems because the part of the computer associated with the automatic trans had a few burns in it also. he feels very confident that the comp is my problem. i got a call today saying it is ready. i will post tomorrow to let everyone know if it starts. thanks everyone.

thanks for all the help guys, the car is a 93 it cranks so i was not thinking of a starter sol. problem. i think that ihave checked all the ground connects but i will look harder. i removed all the fuses one by one to check them, while the battery was disconected so this has erased all the codes.(what luck) i do not know to check a crank sensor but according to the wiring schem. it is not in the ignition loop. i would like to know if a computer going bad is a common occurance because i am new to this group (toyota).

I swapped a coil with my buddy the same day i changed the igniter just to be sure and still no start. thanks

I was driving home one day and it just died. i have the OEM repair manuals and have ohm checked fuel pump,dist., and coil. i have replaced the igniter (with two used ones) from a local yard(150.00) and still no spark. so now i believe it is the ecu but i wanted to get some input from you guys before i shell out another $200.00. Anyone had this problem. Help.