2nd Generation Specific (1986-1992) 1986-1992 Discussion including performance modifications and technical support sections.
Sponsored by:

Need to know about CPU...

Thread Tools
 
Search this Thread
 
Old 05-12-07, 06:28 PM
  #1  
2nd is the first loser!
Thread Starter
 
RX7_Racer_84's Avatar
 
Join Date: Mar 2007
Location: Salem, OR
Posts: 90
Likes: 0
Received 0 Likes on 0 Posts
Exclamation Need to know about CPU...

I need to know what the CPU controls and what the functions are. I have a weird problem w/ my radio and my door warning light flashing while I am driving. The radio wont turn on and turns itself on and off rapidly. Any help or ideas would be great. BTW-I searched and found nothing.
Old 05-12-07, 06:48 PM
  #2  
Senior Member

 
clubber's Avatar
 
Join Date: Apr 2004
Location: South Jordan UT
Posts: 453
Likes: 0
Received 0 Likes on 0 Posts
I'm pretty sure the CPU doesn't control the radio. As far as I know, it controls the horn, turn signals, and some warning buzzers and lights. Someone may know for sure on the small stuff. if you have a factory radio, they are prone to the cold solder joint thing that is common in the cpu and switch gear. Most people, and me too, feel that just changing the radio is the hot setup because it sucks when it's working right and it rarely works right.
Old 05-12-07, 06:56 PM
  #3  
Rotary Enthusiast

 
VacavilleFC's Avatar
 
Join Date: May 2006
Location: Vacaville Ca
Posts: 1,081
Likes: 0
Received 0 Likes on 0 Posts
do you have your radio attached to the stock ground in the radio harness? i've heard that will cause all sorts of problems
Old 05-12-07, 07:19 PM
  #4  
Former Moderator. RIP Icemark.
 
Icemark's Avatar
 
Join Date: Apr 2001
Location: Rohnert Park CA
Posts: 25,896
Likes: 0
Received 19 Likes on 19 Posts
S4 CPU controls:

Horn,
Key lights
Key in door open buzzer
Light on door open buzzer
seat belt not on warnings
Turn signals
brake lights
alternator failure warnings

S5 CPU controls:

Horn,
Key lights
Key in door open buzzer
Light on door open buzzer
seat belt not on warnings
Turn signals
security functions.
High beams (on S5 convertibles).


Radio turning off and on, indicates bad ground or low voltage or a shorted/blown speaker
Old 05-12-07, 07:29 PM
  #5  
2nd is the first loser!
Thread Starter
 
RX7_Racer_84's Avatar
 
Join Date: Mar 2007
Location: Salem, OR
Posts: 90
Likes: 0
Received 0 Likes on 0 Posts
Hmm....ok. The radio only does it when the door light flashes as well. And my clock now resets itself everytime I restart my car. My horn was honking when I turned my car off so I disconnected it. Anyone else have any ideas? I want to replace the CPU just to make sure there isnt an issue there. Also at the same time my factory alarm quit working as well. Its startin to drive me mad....
Old 05-12-07, 07:37 PM
  #6  
Former Moderator. RIP Icemark.
 
Icemark's Avatar
 
Join Date: Apr 2001
Location: Rohnert Park CA
Posts: 25,896
Likes: 0
Received 19 Likes on 19 Posts
what is the voltage in the car when this is happening?

Did you check voltage?
Old 05-12-07, 07:40 PM
  #7  
Senior Member
 
Suiicidalpenguin's Avatar
 
Join Date: Mar 2007
Location: USA/Mass
Posts: 310
Likes: 0
Received 0 Likes on 0 Posts
Sounds like you have a short. Possibly your accessory and battery wires tapping/rubbing. When I was installing my radio I screwed up and tapped the wires together and everything went haywire... well until the room fuse blew.
Old 05-12-07, 11:04 PM
  #8  
2nd is the first loser!
Thread Starter
 
RX7_Racer_84's Avatar
 
Join Date: Mar 2007
Location: Salem, OR
Posts: 90
Likes: 0
Received 0 Likes on 0 Posts
Something else that is weird...When you turn the key to "ACC" nothing happens, nothing gets power that should.....i.e.-radio. I have replaced the ign wiring already with a brand new one from Mazda. Im runnin out of ideas. My wiring harness is unwrapped mostly at the moment. I havent unwrapped the one in the interior yet though. Does anyone have any idea what might have happened? I cant seem to find any crossed wires.
Old 05-13-07, 01:02 AM
  #9  
Former Moderator. RIP Icemark.
 
Icemark's Avatar
 
Join Date: Apr 2001
Location: Rohnert Park CA
Posts: 25,896
Likes: 0
Received 19 Likes on 19 Posts
again what is the voltage.

Man why are all these newbies posting and failing to answer the most basic of all questions???
Old 05-13-07, 01:11 AM
  #10  
Shpee

iTrader: (6)
 
JCurry's Avatar
 
Join Date: Jan 2004
Location: Tx
Posts: 1,948
Received 0 Likes on 0 Posts
Ide say a bad ground.
Old 05-13-07, 02:03 PM
  #11  
2nd is the first loser!
Thread Starter
 
RX7_Racer_84's Avatar
 
Join Date: Mar 2007
Location: Salem, OR
Posts: 90
Likes: 0
Received 0 Likes on 0 Posts
The voltage to the radio is 12v.
Old 05-13-07, 02:04 PM
  #12  
2nd is the first loser!
Thread Starter
 
RX7_Racer_84's Avatar
 
Join Date: Mar 2007
Location: Salem, OR
Posts: 90
Likes: 0
Received 0 Likes on 0 Posts
How many grounds are located under the intake manifold?
Old 05-13-07, 11:56 PM
  #13  
Former Moderator. RIP Icemark.
 
Icemark's Avatar
 
Join Date: Apr 2001
Location: Rohnert Park CA
Posts: 25,896
Likes: 0
Received 19 Likes on 19 Posts
Originally Posted by RX7_Racer_84
The voltage to the radio is 12v.
how do you know?

If the car is not running it should be 12.6 volts, and if the car is running it should be 14.4 volts.

So I suspect you didn't really check.

And if you didn't check, why do you think anyone should help you?
Old 05-14-07, 01:10 AM
  #14  
2nd is the first loser!
Thread Starter
 
RX7_Racer_84's Avatar
 
Join Date: Mar 2007
Location: Salem, OR
Posts: 90
Likes: 0
Received 0 Likes on 0 Posts
I checked it w/ a multimeter. Im not an idiot. It showed over 12v. I found that the memory wire for the radio is connected to the part of the wire harness that has a short or an odd ground problem. I rewired a new wire to the battery for the radio. I still have to sort out why the alarm, door warning light, and the interior lights are inop. I didnt list voltage because I knew it wasnt the issue.
Old 05-14-07, 02:02 AM
  #15  
Winter sucks

 
micah's Avatar
 
Join Date: Jan 2004
Location: Newberg, Oregon
Posts: 3,083
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by Icemark
And if you didn't check, why do you think anyone should help you?
Somebody miss their yoga class?

RX7_Racer: Make sure you fuse-protect that new radio wire you ran. If you don't, you may end up with a bigger headache than you currently have now.

Also... You live in salem.. Nice to see another Oregon player. I'm in Newberg... a hop skip and a jump away.
Old 05-14-07, 02:23 AM
  #16  
Rotary Enthusiast

 
apreludem's Avatar
 
Join Date: Oct 2002
Location: houston
Posts: 905
Likes: 0
Received 0 Likes on 0 Posts
you are having the exact same problem as me...the radio cuts on and off and the clock restarts itself whenever i start my car ...
Old 05-14-07, 09:08 AM
  #17  
Rotary Enthusiast

 
apreludem's Avatar
 
Join Date: Oct 2002
Location: houston
Posts: 905
Likes: 0
Received 0 Likes on 0 Posts
out of curiousity..you did check the fuses under the driver's side right? ...there should be a 7.5 fuse that controls the interior lights....i just changed mine and my problem is solved. it should be the one that is sitting higher then the rest of them.

Last edited by apreludem; 05-14-07 at 09:23 AM.
Old 05-14-07, 06:07 PM
  #18  
2nd is the first loser!
Thread Starter
 
RX7_Racer_84's Avatar
 
Join Date: Mar 2007
Location: Salem, OR
Posts: 90
Likes: 0
Received 0 Likes on 0 Posts
I took the fuse out and my tach and dash instruments quick working. So I figured that the fuse was fine. I havent tried to replace it. The radio works great and is still fused through the fuse box because it still turns on only when you turn the key to "ACC"....My door warning light is now off because I turned my interior light to the "OFF" position instead of the "ON WHEN DOOR IS OPEN" position.
Old 07-22-07, 10:24 PM
  #21  
2 Rotors, 1 Turbo

 
MidnightOwl's Avatar
 
Join Date: Feb 2004
Location: Atlanta, GA
Posts: 1,099
Likes: 0
Received 0 Likes on 0 Posts
Check your door trigger. It's probably doing something real dumb.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
demongo
1st Generation Specific (1979-1985)
7
10-29-12 03:16 PM
liebherk
New Member RX-7 Technical
7
08-30-10 06:24 PM



Quick Reply: Need to know about CPU...



All times are GMT -5. The time now is 07:54 AM.