Sr20det will not shut off. - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

Mildviolence · 01-20-2015, 11:00 PM

Hey just bought a car with a sr20 redtop engine in it. I am having a issue with the motor shutting off when I shut of the key. The engine and all the dash lights are still on. I tried using kill switch and motor still runs even after switching that off. The only way it shuts off is if I put it in 5th and slowly let out clutch and kill it.

I imagine it is the ignition switch however wondered if anyone else has advice or has seen this problem. Thanks.

killer240 · 01-21-2015, 12:16 AM

What electronic devices do you have?

navans14 · 01-21-2015, 01:39 AM

turbo timer

Mildviolence · 01-21-2015, 06:36 AM

No turbo timer. It's a completely stock redtop sr20

blkvrtswp · 01-21-2015, 07:34 AM

Could be bad diode in the ECU - I've seen it before. I actually have an S13 ECU like that here. Can be fixed if you find someone who knows what they are doing. Pull the fuel pump fuse to shut the engine off.

Mildviolence · 01-21-2015, 08:18 AM

I did remove the ecu and looked for burnt traces and/or components and didn't see anything unusual. I will test the diodes tonight and see if any of them are not functioning properly

Mildviolence · 01-21-2015, 09:43 AM

Inspected ecu front and backside of board. No burnt traces. And multimeter shows diodes are working correctly. Any other ideas?

jedi03 · 01-21-2015, 12:42 PM

I fried ecu once an had that happen...new ecu fixed it

OnTheChip · 01-21-2015, 01:57 PM

With ignition switch OFF, check for voltage at ECU pin 36. If you have 12V there, that wire is being powered from a source other than the ignition switch. That will definitely keep the engine running.

WWWinfernoWWW · 10-15-2017, 10:26 PM

I got same problem on mine, I just put in a different ecu and problem solved, but I still want to fix my old ecu thou, how do you test diodes with multimeter is it just a continuity test ?
Or resistance test ?
If it's resistance how do I know how much each resister has to have

01-20-2015, 11:00 PM	#1
Mildviolence Leaky Injector Join Date: Nov 2013 Location: Iowa Posts: 139 Trader Rating: (3) Feedback Score: 3 reviews	Sr20det will not shut off. Hey just bought a car with a sr20 redtop engine in it. I am having a issue with the motor shutting off when I shut of the key. The engine and all the dash lights are still on. I tried using kill switch and motor still runs even after switching that off. The only way it shuts off is if I put it in 5th and slowly let out clutch and kill it. I imagine it is the ignition switch however wondered if anyone else has advice or has seen this problem. Thanks.

01-21-2015, 12:16 AM	#2
killer240 Post Whore! Join Date: Jun 2009 Location: Pair of dice, Norcal Age: 33 Posts: 2,621 Trader Rating: (24) Feedback Score: 24 reviews	What electronic devices do you have? __________________ REVIEW

01-21-2015, 01:57 PM	#9
OnTheChip Zilvia Junkie Join Date: May 2013 Location: Burgaw, NC Posts: 317 Trader Rating: (0) Feedback Score: 0 reviews	With ignition switch OFF, check for voltage at ECU pin 36. If you have 12V there, that wire is being powered from a source other than the ignition switch. That will definitely keep the engine running. __________________ NismotronicSA - Speed-Density Tuning for Nissans

01-21-2015, 01:39 AM	#3
navans14 Leaky Injector Join Date: Jul 2011 Location: 951 CA Age: 34 Posts: 115 Trader Rating: (5) Feedback Score: 5 reviews	turbo timer

01-21-2015, 06:36 AM	#4
Mildviolence Leaky Injector Join Date: Nov 2013 Location: Iowa Posts: 139 Trader Rating: (3) Feedback Score: 3 reviews	No turbo timer. It's a completely stock redtop sr20

01-21-2015, 07:34 AM	#5
blkvrtswp Zilvia Addict Join Date: Oct 2012 Location: NY Posts: 691 Trader Rating: (9) Feedback Score: 9 reviews	Could be bad diode in the ECU - I've seen it before. I actually have an S13 ECU like that here. Can be fixed if you find someone who knows what they are doing. Pull the fuel pump fuse to shut the engine off.

01-21-2015, 08:18 AM	#6
Mildviolence Leaky Injector Join Date: Nov 2013 Location: Iowa Posts: 139 Trader Rating: (3) Feedback Score: 3 reviews	I did remove the ecu and looked for burnt traces and/or components and didn't see anything unusual. I will test the diodes tonight and see if any of them are not functioning properly

01-21-2015, 09:43 AM	#7
Mildviolence Leaky Injector Join Date: Nov 2013 Location: Iowa Posts: 139 Trader Rating: (3) Feedback Score: 3 reviews	Inspected ecu front and backside of board. No burnt traces. And multimeter shows diodes are working correctly. Any other ideas?

01-21-2015, 12:42 PM	#8
jedi03 Nissanaholic! Join Date: Jul 2008 Location: albuquerque Posts: 1,836 Trader Rating: (8) Feedback Score: 8 reviews	I fried ecu once an had that happen...new ecu fixed it

10-15-2017, 10:26 PM	#10
WWWinfernoWWW Join Date: Feb 2012 Location: California Age: 48 Posts: 23 Trader Rating: (0) Feedback Score: 0 reviews	I got same problem on mine, I just put in a different ecu and problem solved, but I still want to fix my old ecu thou, how do you test diodes with multimeter is it just a continuity test ? Or resistance test ? If it's resistance how do I know how much each resister has to have