1991 240sx ignition stays on when key is out but car won't run

[my240isdead]

I have a 1991 240sx se that stopped running the other day, and even when I pull the key out of the ignition, my dash lights stay on, and my power windows operate(like the key is in the on position) , but the radio will not work Also, when I try to crank the car it won't start, but the starter does engage and the engine turns over. Please help.

[vancouverbc]

Have a look at the ignition switch. It is located on the opposite side from where key goes in. You have to remove the steering column cover.The pic shows the switch. You need to take off one screw and switch falls out.

[my240isdead]

I checked the ignition switch and it is ok. I even disconnected it completely from the wiring harness and the problem is still the same. Also I started pulling the fuses one at a time from the fuse box under the hood and found one that says FL75A ALT on it that when pulled turns off everything. Thanks.

[NISTECH]

You might have a short in your altenator. pull the wires of the altenator and see if that turns off the dash lights. If it does you need a new altenator.

[my240isdead]

Nope, that didn't help. Also noticed that with the 75A fuse pulled, my hicas light remains lit. I tried starting the car, but it seems like it is getting no fire to the plugs. Any more suggestions are greatly appreciated.

[NISTECH]

Did you remove all the connections on the alternator. At least the plug and the red main terminal?

[my240isdead]

yes I disconnected both wires and the plug.

[NISTECH]

Ok another thing you can try. Swap the EFI or ECCS relay with another relay of the same type and color. This will tell you if the relay is hagin up.

[NISTECH]

Do the same with the ignition relay if it does not work with the ECCS realy. You can do either first. and check.

[my240isdead]

Ok, I am looking at the fuse box cover and do not see either EFI or ECCS labeled on any relay. Could it possibly be in a different location?

[NISTECH]

how about the ignition relay. BTW there is a relay box under the air cleaner

EDIT The Eccs relay is in the relay box located next to the right strut tower.

[my240isdead]

Oh by the way, I relocated my battery to where the air cleaner was and shortened the intake tube to put my k&n filter where the battery goes, but its been that way for over a year now. Also I have pulled all of the relays out of both boxes and the problem is still there.

[NISTECH]

Ok time for clarity as the relays are what powers just about everything.

Are you talking about the warning lights in your dash? i.e. battery,oil,check engine,ect and you are saying those lights are on all the time even when the key is not in the ignition?

Do you have a volt meter and know how to use it?

[my240isdead]

affirmative

[NISTECH]

Ok dude I am going to have to do this in the morning. I am totally spent and the wiring diagrams are all fuzzy to me right now. I need to review the circuit that powers the dash lights and then have you probe certain points of it with a volt meter. I will post where and what you need to probe when I look at it in the morning. I am using a 92 service manual , it should be the same as a 91.

[my240isdead]

Hey thank you so much for your time man. My service manual is for 93-98 and seems to be a little different and not as specific as I need for this problem.

[vancouverbc]

The radio is powered by accessory and the oil/battery light and power windows are powered by the on postition. A bad switch is the most obvious cause. your accessories are not working but all your on functions are on without key. did you actually pull a plug to disconnect the entire switch ? do you have a remote starter? when key is in accessory postion what is the voltage at the blue wire?

Make sure the ignition relay is not stuck in on position. it powers windowsand dash lights etc

I have a 1991 wiring diagram from mitchels but the colours of the start wires are wrong.

Modified by vancouverbc at 11:06 PM 10/15/2005
Modified by vancouverbc at 11:14 PM 10/15/2005

[NISTECH]

Your mitchel only states the wire colors up to the connector on the coloum. The wires actually between the switch and that connector are not listed. It is that way in the service manaul as well. This is because the switch and short harness are considered the component, and the manufacturer of the switch uses different color wires with any rebuild or if the suppier used was changed that too would have different color wires. So they dont include those wire colors in the diagram. That holds true for new cars.

Ok the relay you need to pull is the brown ignition relay in your fuse box in the left kick panel. You need to find another relay in one of the relay centers that is the same design and color. Swap it into that spot and see if your problem is resolved. That relay is what powers the dash lights and the power windows. Since that is the exact components that are still functioning I suspect it. Its either the relay or a wire to the relay is shorted to power as the relay gets power from the ignition switch when it is turned to the on position. I have a feeling you did not pull that relay when you pulled all the ones under the hood.

[my240isdead]

Ok, I pulled the brown relay out, plugged it back in and the problem is gone, but just for my info, I took a reading across the resistor and it was about 70 ohms. Is that what it should read? Thanks for the help.

[NISTECH]

You mean the relay? It should be around 40 to 50 ohms. Sounds like you got a bad relay.

[vancouverbc]

Your mitchel only states the wire colors up to the connector on the coloum. The wires actually between the switch and that connector are not listed. It is that way in the service manaul as well. This is because the switch and short harness are considered the component, and the manufacturer of the switch uses different color wires with any rebuild or if the suppier used was changed that too would have different color wires. So they dont include those wire colors in the diagram. That holds true for new cars.

.

Thanks. Good to know. Nice job.

[my240isdead]

Hey it's me again. Car ran for about 20 mins then broke down again about 200 yards from my house(lucky for me). I pulled the relay and checked the resistance it was up around 85 ohms and warm to the touch and causing the same problem, but when my HICAS light is staying on with it out. Do you still think it is the problem or could it have cause a failure somewhere else as well.

Thanks

[NISTECH]

Is your key out when the hicas light is on.

Also see if you have another brown relay like that in the car you can swap in there. Pic something non detrimental to vehicle operation if possible.

[my240isdead]

Yes, the key is out when the hicas light is lit. I looked for another of the same type and can't find one in either of the two fuse boxes under the hood or behind the driver side kick panel. Could there be any more places I can possibly find one. If not, I think I am going to find me a wrecked nissan in a salvage yard and scavenge one tomorrow.

[NISTECH]

Take an ohm meter and try to find the lowest ohm checked relay with out going below 40ohms.

[NISTECH]

Your hicas warning light is on the same switched power but on a different circuit from the fuse box. You may have a short to constant power in your fuse box. Lats find out if the short is before or after the fuse box. pull the fuse in the kick panel fuse box. It is the one on the right side at the bottom of the fuse box. Do this when the problem is occuring and the key is out of the ignition. It would be best to do it when the other lights are not having the problem.

[my240isdead]

hey, just for a little more info. The power windows and locks are still operating as well.

[my240isdead]

Ok, I went the junkyard and found another relay exactly like mine and it has the same resistance reading as mine, but I bought it anyway. I pulled that fuse like you instructed and the HICAS light did go out, but with both relays the dash lights, door alarm, seatbelts, all are on even with that fuse pulled.

thanx

[vancouverbc]

Power for the windows is coming into ignition relay from the green fuse link in the relay box via door timer. Try pulling the green fuse link.


Modified by vancouverbc at 12:53 AM 10/18/2005

[my240isdead]

Hello again,