Airbag Install

Got questions about your Nissan? We're here to help, and it's FREE!
AARONDW
Posts: 23
Joined: Wed Feb 18, 2004 1:22 pm

Post

ANYONE KNOW WHERE I CAN FIND DIRECTIONS ON HOW TO PROPERLY INSTALL NEW AIRBAGS.

THANKS


NISTECH
Posts: 10585
Joined: Sun May 25, 2003 4:17 am

Post

disconnect the battery for 10 mins before starting to mess with them, then it is simply unbolt and reinstall, if your airbags have detinated you also need to replace the control unit.

AARONDW
Posts: 23
Joined: Wed Feb 18, 2004 1:22 pm

Post

NISTECHWHAT IS THE REASON TO WAIT 10 MIN? IS THE CONTROL UNIT ALSO CALLED COMPUTER?

AARONDW
Posts: 23
Joined: Wed Feb 18, 2004 1:22 pm

Post

WHERE IS THE CONTROL UNIT LOCATED ?

NISTECH
Posts: 10585
Joined: Sun May 25, 2003 4:17 am

Post

You need to wait for the capacitors in the system to power down completely, when you disconnect the battery be sure to disconnect both battery terminals too. The reason you need to wait is it takes less then 3 v with no amperage to detinate the bags. if you get an arch from a still charged capacitor BANG your air bag could explode in your hands possibly removing them from the arms they were once attached to. Air bags are explosives so handle them with caution.

The control unit is usually located under the center consol near the rear.

NISTECH
Posts: 10585
Joined: Sun May 25, 2003 4:17 am

Post

Oh it is typically referred to as the diagnostic sensor unit.

AARONDW
Posts: 23
Joined: Wed Feb 18, 2004 1:22 pm

Post

So is 10 min enuff to power down the system? Is there a way to check the voltage prior to connecting the harness? If so where do I check the voltage from?

NISTECH
Posts: 10585
Joined: Sun May 25, 2003 4:17 am

Post

DO NOT probe the air bag circuits, your volt meter has a 9volt battery in it. Actually 3 mins is usually plenty but 10 is on the safe side. another trick to fully discharge residule voltage is to touch the battey cables together after they are off the battery.

AARONDW
Posts: 23
Joined: Wed Feb 18, 2004 1:22 pm

Post

So touching the cables togather will discharge the voltage?I guess I will be wearing my helmet and riding jacket when I install.

AARONDW
Posts: 23
Joined: Wed Feb 18, 2004 1:22 pm

Post

Is there a SURE way to know what the voltage is in the system?

NISTECH
Posts: 10585
Joined: Sun May 25, 2003 4:17 am

Post

yea its gone if you leave it disconnected for 10 mins, you'll be fine.

AARONDW
Posts: 23
Joined: Wed Feb 18, 2004 1:22 pm

Post

Can you give me step by step instructions ?

NISTECH
Posts: 10585
Joined: Sun May 25, 2003 4:17 am

Post

pretty much did, start by disconnecting the battery, go slam a Root beer come back and start by disconnecting the old connectors, remove the couple of bolts holding them in lift the old bags out drop the new ones in ,put the bolts back in. finish up in the interior, go connect the battery back up. With your door open reach in from under the steering wheel and turn your key on if they dont go bang your all good.

You will need a special tamper proof torx socket to remove the air bag bolts and 3 of the diagnostic sensor unit bolts. I thing its a T50 or T55 tamper proof bit.

AARONDW
Posts: 23
Joined: Wed Feb 18, 2004 1:22 pm

Post

All I have to do is put em back in, I got the torx sockets, just wanna make sure I dont blow my *** up, after all I did my time as a marine, would hate to come home and get blown up doing this crap.

navysnail
Posts: 3335
Joined: Wed Feb 11, 2004 1:33 pm
Car: 1990 Nissan 240SX fastback

Post

lol, youll be fine, like NISTECH said, reach around under the wheel and turn it on the first time, so if somehow they would manage to trigger, you would be out of their path

quick question: what does triger the airbags, is there a shock sensor that detects sudden deceleration in the control unit, or what

AARONDW
Posts: 23
Joined: Wed Feb 18, 2004 1:22 pm

Post

240The sensor is up front under the grill.

navysnail
Posts: 3335
Joined: Wed Feb 11, 2004 1:33 pm
Car: 1990 Nissan 240SX fastback

Post

ahhh, always wondered about that one

did you get thoes bombs, um er... airbags installed

AARONDW
Posts: 23
Joined: Wed Feb 18, 2004 1:22 pm

Post

That job will be done next week, I was looking for info on how to install ect.... I have never installed this crap before, so just being VERY cautious.

navysnail
Posts: 3335
Joined: Wed Feb 11, 2004 1:33 pm
Car: 1990 Nissan 240SX fastback

Post

yeah, lol ive done them in school last year, we unhooked the batery (ground only) pulled the fuse to the airbag control unit (im not sure if 240's have a fuse, but NISTECH didnt tell you to pull one, so dont worry about it)it took like 10 minutes to get the screws from the back out, then we unhooked the airbag, lol not very cautious

btw that was in a buick

AARONDW
Posts: 23
Joined: Wed Feb 18, 2004 1:22 pm

Post

That job will be done next week, I was looking for info on how to install ect.... I have never installed this crap before, so just being VERY cautious.

NISTECH
Posts: 10585
Joined: Sun May 25, 2003 4:17 am

Post

240kid wrote:lol, youll be fine, like NISTECH said, reach around under the wheel and turn it on the first time, so if somehow they would manage to trigger, you would be out of their path

quick question: what does triger the airbags, is there a shock sensor that detects sudden deceleration in the control unit, or what


The sensor under the grille is a satelite sensor, the one under the center console has the G force sensor in it. This sensor detects rapid deceleration, like 15mph per second or some strange number like that will cause the bags to detinate. On newer vehicles there are variables to when and how a bag is detinated, but on cars like yours its pretty much determined just by the sensor under the center console.

I have seen and heard of incedents where the bags have deployed on technicians and other service personnel that would blow your mind.couple examples here, Years ago around late 80's I worked for a goodyear store, one of the techs was hunkered over the steering wheel working on the steering coloum in a cadillac when he peirced one of the airbag wires and BANG he go blown back into his seat and had a rough time regaining his ability to breath.Another incedent I heard about was 2 guys I worked with in a nissan dealer where working on an airbag system in a altima I think it was . One of them was in the drivers seat doing something and the other was working with the control unit under the center consule,key was on, he lifted the control unit up and tilted it sideways and BANG the guy in the drivers seat got hit by it left a pretty good laceration in his face and he couldnt hardly hear for 3 days. last one here I heard in tech school an xterra was in for a rattle while driving and the tech was struggling to find this rattle so the service manager got in volved and they decided the best way to find this rattle was to have the service manager climb into the truck and raise him up on a rack while the tech used a hammer underneath to recreate the rattle, well the service manager is in the car with the windows up and his ears tuned in to find even the slightes noises when bang all the airbags and seatbelt pretensioners go off. gotta laugh at that last one just imagining the boss up in the air in the car your working on and you hear the explosion and realize you just set all the explosives off in the car. You stand there trying to decide"do I let the car down and see if hes ok or do leave him there lock up my box and go home?"


Return to “Nissan Online Mechanic”