[RaPtOr2003]

just as the title says, i was driving earlier this evening, when all of a sudden the dash lit up and then went out, but the ABS and Airbag light come on ONLY when im on the accelerator, at a light those lights go off and everything looks as normal? also no juice to my amp in the trunk, so i checked engine codes, n cleared evap code lol, then disconnected the battery for a few min, went for a drive again and same thing , ABS and airbag light comes on when accelerating. by the way its a 01 SE. thanks

 

[i68k]

that sounds odd. did you pull the codes and get something relevant to the abs or airbag codes? i think you need a special code reader to see the abs codes.

go over and check your battery terminal for tightness and good ground contact. check you battery voltage motor on&off.

 

[RaPtOr2003]

ya its weired pulled no releavent codes, just evap, and heater 02, went and bought a new battery (had stock nissan battery still lol) but to no avail, battery should be good for while now tho :/

 

[i68k]

not sure why you got a new battery? you shouldve just checked your voltage with motor on&off. this will check your charging systems operation or show there's missing voltage somewhere from a bad connection or something. usually alternator is brake and battery lights, but thats not your problem. did you look thru the fsm already? its a free download around here somewhere, you should check it out, the answer might be there in black and white. im not at home, ill check next time if you dont find it.

 

[RaPtOr2003]

not sure why you got a new battery? you shouldve just checked your voltage with motor on&off. this will check your charging systems operation or show there's missing voltage somewhere from a bad connection or something. usually alternator is brake and battery lights, but thats not your problem. did you look thru the fsm already? its a free download around here somewhere, you should check it out, the answer might be there in black and white. im not at home, ill check next time if you dont find it.

awesome thanks, i just did a voltage reading across the terminals with vehicle off and on, off reading normal, on with no load just idling im pulling 17.4V ? holy crap guessing its the altenator not regulating the voltage?

 

[RaPtOr2003]

another update, so voltage at idle is 17.4V and Voltage with all accessories at full blast is 12.5V ................. guess will run all accessories until i find out problem, im guessing alternator since im getting a 17.7V reading, should the alternator limit voltage to no more than 14.4?

 

[i68k]

woah? yea it should be not more than say 15 V with the motor running. what do you get when your motor is off? you should see your battery voltage is 12 V, plus or minus .5. im not sure if your multimeter or whatever your using is accurate, you shouldnt see a 5V difference with accessories, this is a possibility. you should be seeing like 12V motor off and 14ish V motor on. if you are seeing that much of a drain, its possible there's electrical connection failure somewhere like a bad ground or wire insulation issues, possibly a bad ecu or something isnt out of the question.

edit: be sure your battery is 12v, it should be since its new it could be as high as 12.8v. does your idle change when you put all your accessories on except for the ac compressor? your idle should barely move when using accessories, just that kick with the ac. the alternator uses rpm for its charge, so at higher rpm there should be higher voltage. i think there is a regulator somewhere, im not sure where it is.

edit2: did you look thru the fsm for your year/model b15? did you follow both electrical and troubleshooting diagnoses for either abs or airbag? make sure you didnt blow a fuse?

 

[RaPtOr2003]

woah? yea it should be not more than say 15 V with the motor running. what do you get when your motor is off? you should see your battery voltage is 12 V, plus or minus .5. im not sure if your multimeter or whatever your using is accurate, you shouldnt see a 5V difference with accessories, this is a possibility. you should be seeing like 12V motor off and 14ish V motor on. if you are seeing that much of a drain, its possible there's electrical connection failure somewhere like a bad ground or wire insulation issues, possibly a bad ecu or something isnt out of the question.

edit: be sure your battery is 12v, it should be since its new it could be as high as 12.8v. does your idle change when you put all your accessories on except for the ac compressor? your idle should barely move when using accessories, just that kick with the ac. the alternator uses rpm for its charge, so at higher rpm there should be higher voltage. i think there is a regulator somewhere, im not sure where it is.

edit2: did you look thru the fsm for your year/model b15? did you follow both electrical and troubleshooting diagnoses for either abs or airbag? make sure you didnt blow a fuse?

ya motor off there was i think 12.5V across, definatly got to check out the FSM, im pretty sure i have it saved on this computer somewhere, def best to rule out everything before spending any more money! thanks for your help so far def weired with all the accessories running and it being 12.5V at that time the airbag light, ABS and battery light all go out and everything in the ****pit looks normal, except for having everything on lol. will give update when i fire thru the fsm in the morning, thanks again

Edit1: checked all fuses everything good there, more diagnosing to come :/

 

[i68k]

http://www.b15u.com/troubleshooting-support/15474-car-womt-start-abs-airbag-light.html

http://www.b15u.com/troubleshooting-support/16789-dash-lights-came-while-car-running.html

both of these people had both airbag and abs light on, but they had problems with the car actually running unlike you. their problem was the alternator itself, which could be your problem. like said before im not sure where the regulator is, might be inside the alternator?

here is a write-up for your alternator, there should be one on this site too somewhere:
http://www.b15u.com/sentra-specific...ator-belt.html?highlight=replacing+alternator

 

[RaPtOr2003]

ohh thank god u found that post ive been looking for the past few hours where the belt tensioner was, impossible to find anything with the sr20, gonna run out and check it out now, thanks

 

[RaPtOr2003]

also forgot to mention, went out to start car yesterday and battery was dead, def alternator

 

[i68k]

ohh thank god u found that post ive been looking for the past few hours where the belt tensioner was, impossible to find anything with the sr20, gonna run out and check it out now, thanks

oops, my bad, that alternator how-to is for the qr25, not the sr20. im not sure if your sr20 had an auto-tensioner or manual tensioner. if its manual tensioner, there should be like a threaded rod with a bolt somewhere, most likely pushing on the idler pulley. make sure your belt is tight, if your belt was loose, it may not have been spinning the alternator pulley. if you loose the threaded rod and the pulley doesnt loosen the belt, you may have to loosen the pulley, its probably bolted to a sliding block.

 

[RaPtOr2003]

been a few days been mega busy was definatly the alternater, changed it out, what a PITA, but everything is running perfect now, thanks for all your help i68k!! karma to u bro!