how about a diagram? im better with a diagram than reading. thanksReset circuit for GS300 '98-00 or IS300 '01 ECU (see pinout):
1) Cut ECU wires E6-1 (BATT) and E6-7 (BM).
2) use relay #1 to connect sides of BATT wire,
use relay #2 to connect sides of BM wire
3) power both relays by E6-9 (IGSW) and E3-17 (GND)
4) Check it - both wires must connected when ignition switch ON and START positions only
You can use this scheme for IS300 '02 and later (see ECU pinout for same signals: BATT, BM, IGSW, GND)
This circuit help yours ECU to work in open-loop determined mode w/o all O2's and check engine light.
Yes, I would think so too. You are already controlling the ECM with the relay's contacts and IGSW energizes the relays. No need to control the ground on the relay's coil, controlling just IGSW is fine. For anyone who doesn't have the wiring schematics for '01 and '02+, here you go below. It's also in the IS300 1300+ page complete diagnostic manual I just put up(not the FSM, just the DI section that hasn't been available till now!)looks to me like it's a ground, can't you just ground it anywhere?
I can surely take a look when I get home, unless you can download and PM me the engine control pdf for '01 as an attachment. What I want to know, does the IGSW briefly become "hot" during cranking and then is not "hot". If it stays hot, then the relays will stay energized and according to the print the contacts will open. If the relays are to remained energized when the ignition is on, then they need to utilize terminals 30 and 87(N.O. Contacts). So the question remains(until I can test), does IGSW only get energized during cranking and then de-energize, allowing power to flow thrue the relays N.C. Contacts(based on the jpg drawing). I need to take a closer look at this. I bet it can be done with one relay, possibly a 5 pin. I'll update my findings.Jason, can you please look at diagram and then follow it on 01 ECU pin diagram. It seems like the information is given wrong. I wired up like this then realize everything is wrong by looking 01 pinout.