Notices
SC - 1st Gen (1992-2000)

Neutral Safety bypass problem

Thread Tools
 
Search this Thread
 
Old Dec 18, 2011 | 06:31 PM
  #1  
97-SC300's Avatar
97-SC300
Thread Starter
Lexus Fanatic
15 Year Member
Liked
Loved
Community Favorite
iTrader: (17)
 
Joined: Jun 2006
Posts: 9,238
Likes: 133
From: Earth
Default Neutral Safety bypass problem

Hey guys, almost done with my 2jzgte aristo swap on my 97 sc300. some background on the swap. Aristo motor into a 97sc300 which is swapped from auto to r154. Dr. Tweak did my harness conversion. using the stock aristo ecu. problem is i tried starting the motor for the first time... and nothing happaned. no click from starter or anything. all inside lights come on in key on position, can hear fuel pump running. but when i turn the key its not doing anything. i searched around and found Biggus thread on how to bypass the neutral safety whitch by running a wire from the starter relay to the white/black wire under the dash. i did that and bam when i turned the key to the on position (not start position) the car turned over and started. ran for 5 seconds until i realized the started would not disengage and the gauge cluster wont light up. so now in stumped on what to do. any help would be awsome at this point.
Reply
Old Dec 19, 2011 | 10:56 AM
  #2  
stockhatch's Avatar
stockhatch
Lexus Champion
iTrader: (12)
 
Joined: May 2009
Posts: 2,544
Likes: 5
From: Raleigh NC
Default

Did tweak totally remove the auto plug, or did he wire it so that the plug is there in case you want to run an auto trans later? If he left it hanging there, you will need to put a little jumper wire between pins 4 and 7 or 4 and 10 to allow the starter to get power.
Reply
Old Dec 19, 2011 | 11:45 AM
  #3  
97-SC300's Avatar
97-SC300
Thread Starter
Lexus Fanatic
15 Year Member
Liked
Loved
Community Favorite
iTrader: (17)
 
Joined: Jun 2006
Posts: 9,238
Likes: 133
From: Earth
Default

its totally removed...any other suggestions
Reply
Old Dec 19, 2011 | 11:58 AM
  #4  
stockhatch's Avatar
stockhatch
Lexus Champion
iTrader: (12)
 
Joined: May 2009
Posts: 2,544
Likes: 5
From: Raleigh NC
Default

Check for continuity between pin 6 on connector IJ1, and pin 3 on connector EB1.
Reply
Old Dec 19, 2011 | 12:22 PM
  #5  
97-SC300's Avatar
97-SC300
Thread Starter
Lexus Fanatic
15 Year Member
Liked
Loved
Community Favorite
iTrader: (17)
 
Joined: Jun 2006
Posts: 9,238
Likes: 133
From: Earth
Default

Would you know where those connectors are located?
Reply
Old Dec 19, 2011 | 02:30 PM
  #6  
stockhatch's Avatar
stockhatch
Lexus Champion
iTrader: (12)
 
Joined: May 2009
Posts: 2,544
Likes: 5
From: Raleigh NC
Default

Passenger kick panel for IJ1. It is the square shaped grey connector.

EBI, I think plugs into the fuse box in the engine bay, but I dont remember exactly.... It is an 8 pin roundish/oval connector.





.
Attached Thumbnails Neutral Safety bypass problem-eb1.jpg  
Reply
Old Dec 19, 2011 | 02:47 PM
  #7  
97-SC300's Avatar
97-SC300
Thread Starter
Lexus Fanatic
15 Year Member
Liked
Loved
Community Favorite
iTrader: (17)
 
Joined: Jun 2006
Posts: 9,238
Likes: 133
From: Earth
Default

Thank you, what does this wire control?
Reply
Old Dec 19, 2011 | 03:58 PM
  #8  
stockhatch's Avatar
stockhatch
Lexus Champion
iTrader: (12)
 
Joined: May 2009
Posts: 2,544
Likes: 5
From: Raleigh NC
Default

Neutral/park bypass circuit. If you have continuity, you may have an issue farther down the line. If you have open between them, jumper them and you should be good to go.

Either way, to be safe I would contact Dr Tweak and let him know what is going on. He may have done something different with your harness and he would know better than I what needs to be done to remedy the no start issue.

I am offering my advice for free, and I only warranty it up to the purchase price
Reply
Old Dec 19, 2011 | 04:28 PM
  #9  
97-SC300's Avatar
97-SC300
Thread Starter
Lexus Fanatic
15 Year Member
Liked
Loved
Community Favorite
iTrader: (17)
 
Joined: Jun 2006
Posts: 9,238
Likes: 133
From: Earth
Default

thnaks man. i contacted dr. tweak he told me that there is no bypass needed on their harnesses and had me do some checks on the starter relay. seems like i have no power going to the starter relay when the key is in the start position. but i have good ground from the relay. now im really stumped
Reply
Old Dec 20, 2011 | 05:31 AM
  #10  
stockhatch's Avatar
stockhatch
Lexus Champion
iTrader: (12)
 
Joined: May 2009
Posts: 2,544
Likes: 5
From: Raleigh NC
Default

Well, the circuit I referenced is what triggers the starter relay, so I still suspect it. I would pull those two plugs and check for continuity between those pins just to be sure. That circuit creates a bridge directly between the starter relay and the ignition switch, so it's a pretty simple circuit.
Reply
Old Dec 20, 2011 | 05:48 AM
  #11  
97-SC300's Avatar
97-SC300
Thread Starter
Lexus Fanatic
15 Year Member
Liked
Loved
Community Favorite
iTrader: (17)
 
Joined: Jun 2006
Posts: 9,238
Likes: 133
From: Earth
Default

How can i check for continuity from under the hood to under the dash? Any suggestions, i have a standard voltmeter
Reply
Old Dec 20, 2011 | 06:21 AM
  #12  
stockhatch's Avatar
stockhatch
Lexus Champion
iTrader: (12)
 
Joined: May 2009
Posts: 2,544
Likes: 5
From: Raleigh NC
Default

Use a scrap piece of wire. Strip the ends and connect one end under the hood. Then string the other end into the cabin and use your voltmeter between that and the other connector. To make it easier under the hood, you dont have to unplug the connector itself. You can just pull out the starter relay and stick the end of the wire into pin 1. To find pin one, use the diagram on top of the relay. I think it is the pin closest to the front of the car.

I would pull the battery cables when you do all this. You don't want to touch the wrong thing and engage the starter.
Reply
Old Dec 20, 2011 | 06:26 AM
  #13  
stockhatch's Avatar
stockhatch
Lexus Champion
iTrader: (12)
 
Joined: May 2009
Posts: 2,544
Likes: 5
From: Raleigh NC
Default

You can also pull the ST fuse in the drivers kick panel fuse box and check for continuity between there and pin 1 of the starter relay that I mentioned. Essentially, you are checking to verify that the ST circuit(which gets power when the key is turned) is connected to pin 1 of the starter relay(which controls the starter itself).
Reply
Old Dec 20, 2011 | 06:26 AM
  #14  
97-SC300's Avatar
97-SC300
Thread Starter
Lexus Fanatic
15 Year Member
Liked
Loved
Community Favorite
iTrader: (17)
 
Joined: Jun 2006
Posts: 9,238
Likes: 133
From: Earth
Default

Thank you so much man, looks like ur the only one here to help lol ill see what that comes up with
Reply
Old Dec 21, 2011 | 04:43 PM
  #15  
97-SC300's Avatar
97-SC300
Thread Starter
Lexus Fanatic
15 Year Member
Liked
Loved
Community Favorite
iTrader: (17)
 
Joined: Jun 2006
Posts: 9,238
Likes: 133
From: Earth
Default

dr. tweak had me check for continuity from the IJ1 connector from the black/white wire to pin 77 of the harness side of the ecu. i have none. what now
Reply



All times are GMT -7. The time now is 08:31 AM.