(ELECTRICAL) No Relay's? What was Mazda thinking?
#1
(ELECTRICAL) No Relay's? What was Mazda thinking?
So here goes. '82 GSL. Always had trouble with the ignition switch. Sometimes the engine would run but wouldn't power the trailing coil or tach till you bumped the key. Radio would cut in and out. Voltage would rarely be above 12.
Got the alternator sorted out. Bought a brand new ignition switch from Mazda. 6 months later the voltage didn't climb higher than 11, alternator was putting out 14v and all grounds were excellent. Battery cables replaced, fuse links replaced with box of real fuses, etc.
Check voltage into the switch, 14v. Out of the switch, 12v!!!! I pulled the switch apart and all the contacts were almost arc-ed to nonexistance! I took my old switch apart, and it was just like the power window switches, in good shape but corroded. Cleaned the contacts and soldered the rivets to the wire leads since I noticed on the new switch, you could spin the wire around the rivet. Finally I got 13.5v on the gauge and only .5v drop! month later, back down to 12.
Why did Mazda decide to run ALL the power through these horribly designed switches?
So I got my hands on 4-70amp relays from work and installed them to handle the load of the switch for the 4 switched leads. I turned the switch into a negative relay trigger lead. I ran a new high strand count 8ga wire in place of the white/red stripe feed wire.
Finished up today.
13v on the gauge (so the gauge def doesn't work right) as I have 14.7V at the relays in/out. The windows work faster, the blower motor blows harder, and the car actually increased in idle from 750 where I had it tuned, to 1100!!!!! Amazing what happens when the ignition coils get full voltage! Efficiancy!
I'll post pictures later this week. Just wanted to post about this! I did searches and didn't find anyone with ignition switch problems like this!
Got the alternator sorted out. Bought a brand new ignition switch from Mazda. 6 months later the voltage didn't climb higher than 11, alternator was putting out 14v and all grounds were excellent. Battery cables replaced, fuse links replaced with box of real fuses, etc.
Check voltage into the switch, 14v. Out of the switch, 12v!!!! I pulled the switch apart and all the contacts were almost arc-ed to nonexistance! I took my old switch apart, and it was just like the power window switches, in good shape but corroded. Cleaned the contacts and soldered the rivets to the wire leads since I noticed on the new switch, you could spin the wire around the rivet. Finally I got 13.5v on the gauge and only .5v drop! month later, back down to 12.
Why did Mazda decide to run ALL the power through these horribly designed switches?
So I got my hands on 4-70amp relays from work and installed them to handle the load of the switch for the 4 switched leads. I turned the switch into a negative relay trigger lead. I ran a new high strand count 8ga wire in place of the white/red stripe feed wire.
Finished up today.
13v on the gauge (so the gauge def doesn't work right) as I have 14.7V at the relays in/out. The windows work faster, the blower motor blows harder, and the car actually increased in idle from 750 where I had it tuned, to 1100!!!!! Amazing what happens when the ignition coils get full voltage! Efficiancy!
I'll post pictures later this week. Just wanted to post about this! I did searches and didn't find anyone with ignition switch problems like this!
#2
RX HVN
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obv you are a bit of an electrical Wiz!
I think it is safe to say that, barring some European cars of The Day, most manufacturer's electrics were marginal to the multi-tasking they were asked to perform. I was stunned to find some dozen+ relays neatly laid out (in one place, what a concept!) in my 82 SAAB that protected virtually _every_ circuit!
Congrats on chasing down what for many (well, me anyway) would be a Heroic task. PLEASE! do detail what and how you did it so we electric-newbies can follow and benefit!!!
Thanks for sharing. This is what makes this forum so amazing...
Stu Aull
80GS (no electric issues - yet!)
Alaska
I think it is safe to say that, barring some European cars of The Day, most manufacturer's electrics were marginal to the multi-tasking they were asked to perform. I was stunned to find some dozen+ relays neatly laid out (in one place, what a concept!) in my 82 SAAB that protected virtually _every_ circuit!
Congrats on chasing down what for many (well, me anyway) would be a Heroic task. PLEASE! do detail what and how you did it so we electric-newbies can follow and benefit!!!
Thanks for sharing. This is what makes this forum so amazing...
Stu Aull
80GS (no electric issues - yet!)
Alaska
#7
So here are some pictures of what we are trying to avoid. Keep in mind this is an OEM Mazda switch brand new 6 months ago. Semi Daily driven and always garaged.
The Copper contacts are worn almost through, and the leads on the back that are riveted through, could spin. Not good for electrical connections.
The Copper contacts are worn almost through, and the leads on the back that are riveted through, could spin. Not good for electrical connections.
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#8
So I soldered the rivets in place. You'll need a high wattage iron for this. It's alot of heat and you want the heat to get there fast so you don't soak the part and melt the plastic.
Carefully take the plastic white switch cover off. Hold the white cup downward, thatway all the copper components stay in place and come off with it. Take pictures, then take each piece off and use some light sand paper to clean the corrosion off. Add some dielectric grease for protection and lubrication and reassemble.
Here's a picture of the Fuse Box I installed after reading up on the 2nd gen box. This one is from a B2200 Carbed Mazda Truck and fit perfectly with a little bracket I made off the stock plug wire bracket.
I replaced the white/red striped "MAIN" wire from that fuse box, with a car amp 8ga multi strand power wire.
The relay Boxes are COLE HERSEE (I can get part numbers at work tomorrow) and the Relays are 4 post, 70amp relays. They have two LARGE leads to handle more load than your usual 30/40 amp relays. The 8 GA wire from the fuse box splits into 4-10 ga leads one for each relay. And then from the relay 10ga wire to the original switch output leads. (Diagram to come).
Carefully take the plastic white switch cover off. Hold the white cup downward, thatway all the copper components stay in place and come off with it. Take pictures, then take each piece off and use some light sand paper to clean the corrosion off. Add some dielectric grease for protection and lubrication and reassemble.
Here's a picture of the Fuse Box I installed after reading up on the 2nd gen box. This one is from a B2200 Carbed Mazda Truck and fit perfectly with a little bracket I made off the stock plug wire bracket.
I replaced the white/red striped "MAIN" wire from that fuse box, with a car amp 8ga multi strand power wire.
The relay Boxes are COLE HERSEE (I can get part numbers at work tomorrow) and the Relays are 4 post, 70amp relays. They have two LARGE leads to handle more load than your usual 30/40 amp relays. The 8 GA wire from the fuse box splits into 4-10 ga leads one for each relay. And then from the relay 10ga wire to the original switch output leads. (Diagram to come).
#9
Right near Malloy
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Archiving.
I have seen relay threads regarding the power windows and threads regarding the headlights...
This is the most extensive use of relays I've seen.
I never looked through the first gen electrical schematic, but I had assumed it had a main relay.
Good work.
I've subscribed and will update the archive as more info gets added.
Now:
I believe you can go to more commonly available 40 amp relays instead of the 70 amp units.
I don't believe everything in the car takes 70 amps.
Starter should only run the starter solenoid; solenoid should handle the power to the starter itself. (Which takes many hundreds of amps.)
Ign 1 and 2 might warrant the 70 amps.
ACC runs the stereo and cigarette lighter. Not much draw there.
Also, you can use the FC fuse block which has been discussed in other threads. It's about the only thing that FCs are good for aside from ignition components.
I have seen relay threads regarding the power windows and threads regarding the headlights...
This is the most extensive use of relays I've seen.
I never looked through the first gen electrical schematic, but I had assumed it had a main relay.
Good work.
I've subscribed and will update the archive as more info gets added.
Now:
I believe you can go to more commonly available 40 amp relays instead of the 70 amp units.
I don't believe everything in the car takes 70 amps.
Starter should only run the starter solenoid; solenoid should handle the power to the starter itself. (Which takes many hundreds of amps.)
Ign 1 and 2 might warrant the 70 amps.
ACC runs the stereo and cigarette lighter. Not much draw there.
Also, you can use the FC fuse block which has been discussed in other threads. It's about the only thing that FCs are good for aside from ignition components.
#10
I used 70 amp relays because if you add up the total potential amperage (IE The fuse totals) you get close to or over 40 amps. I wanted the safety. AND being in the industry for years, those little 30-40 amp relays die more often than the larger 70 amp relays.
In addition, the starter solenoid itself can run upto 70amps itself. Why not build it overkill if you're going to do it?
ACC also runs the blower motor! 20amp fuse, and the defroster 15amp fuse, power antenna/radio 20amp fuse, both wiper motors 10amp each. See what I mean, the "potential" adds up quick. The small 10ga wire powering all bits of the car except the headlights is rediculous.
IGN 2 has the power windows 30amp, mirrosr 10 amp,
I'm sure you could use any fuse block. I used was was easy and accessible. FCs are non-existant in yards around here.
In addition, the starter solenoid itself can run upto 70amps itself. Why not build it overkill if you're going to do it?
ACC also runs the blower motor! 20amp fuse, and the defroster 15amp fuse, power antenna/radio 20amp fuse, both wiper motors 10amp each. See what I mean, the "potential" adds up quick. The small 10ga wire powering all bits of the car except the headlights is rediculous.
IGN 2 has the power windows 30amp, mirrosr 10 amp,
I'm sure you could use any fuse block. I used was was easy and accessible. FCs are non-existant in yards around here.
#11
I should point out this is on my '82 GSL 12A Carbed. Wiring might be different for other years but the concept is the same.
The relay blocks from CH also interlock together which is nice.
If wired like this, you'll need to come up with solder butt connectors of appropriate sizes to do what you need to do. Also, this way allows the ignition switch to be replaceable like stock (Not that you'll need to now) but it utilized the original connectors so it just unclicks and removes.
The relay blocks from CH also interlock together which is nice.
If wired like this, you'll need to come up with solder butt connectors of appropriate sizes to do what you need to do. Also, this way allows the ignition switch to be replaceable like stock (Not that you'll need to now) but it utilized the original connectors so it just unclicks and removes.
#12
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crappy contacts... well ok, but do remember that your ride is now 28 yrs old... and only really designed to work until the 3 year warranty was up.
Good job on the rewiring writeup. A relay stuck on is the last thing you want, so always error on the larger side. And remember the inrush current on the headlights is about 10x the rating when warm (35W lamp @ 12V = 2.9A, inrush will be over 30 per lamp).
Good job on the rewiring writeup. A relay stuck on is the last thing you want, so always error on the larger side. And remember the inrush current on the headlights is about 10x the rating when warm (35W lamp @ 12V = 2.9A, inrush will be over 30 per lamp).
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