Heated seats won't work

[Vanished]

Ok, so. i cleaned out the switch, and the green a blue wires have continuity when the switch is on, not when it's off. so those are ok, both of them

The seats are connected

The switchs are connected.

Is the a fuse anywere? i looked but couldn't find anything..?

red light on the the switch does not come on, so i'm assuming there is no power to the switch...(fuse?)

[wytbishop]

I have identical symptoms in my heated seats. We need to figure this out. My a-- is cold.

It's possible that a broken element in the seat could break the entire circuit including the switch light, but I expect that there must be a fuse as its a heating element and without a fuse there would be a safety issue. I have not yet been able to find a manual which shows the heated seat electrical circuit. I bought a 93 manual on AllData.com but it's American and doesn't show the heated seats.

[Vanished]

BUMP

anyone else? This is making me rather angry at the moment..i'm gonna keep searching the forum, i'll see what i come up with.

[umcamara]

Have you tested for +12 volts at the switch and at the harness for the seat? How about ground at the seat harness?

You can try temporarily connecting +12 volts and ground directly to the seat harness, just to see if it does heat. That way you can localize the problem area.

Is it a universal three terminal switch you're using? Have you grounded the switch?

I'm not familiar with the heated seat system, but I would assume that there would be a relay somewhere that the switch is triggering because the seats probably draw a decent amount of current.

[wytbishop]

I was told by a somewhat reliable source that there is no relay in the system, though I don't know myself if I believe it.

If I unplug the seat harness shouldn't there be continuity through the heating element?

[umcamara]

I was told by a somewhat reliable source that there is no relay in the system, though I don't know myself if I believe it.

If I unplug the seat harness shouldn't there be continuity through the heating element?

Yes. Generally with a heating element there is very little resistance, I think in the milli-ohm range.

[Vanished]

Ok well i searched the forum up and down, nothing. Also the water pumpe exploded and i'm to lazy to fix it so it's in the shop right now, anyway i'll get back to you guys and see what i can find out, i'll be testing for power at the harness right away.

[sk8erdude802]

[quote="wytbishop"]We need to figure this out. My a-- is cold.
quote]

Thats funny cause most of us are not as lucky as the two of you. We never got to have heated seats. Common mazda your letting me down. I feel left out. I want heated seats.

Steve-O

[Dark_Rider2k3]

I didn't even know there were MX-ers with heated seats

LUCKY!!

[umcamara]

I didn't even know there were MX-ers with heated seats

LUCKY!!

'93 Special Editions came with heated leather seats, and other goodies. Unfortunately (no offense to anybody who has one, this is just my useless opinion) they were only available in a ghastly raspberry metallic (purple) paint. There are though, ones in a couple different colors.

[wytbishop]

So I had to take my 3 in for it's 14,000km inspection today and while I was there I asked to see their 93' shop manual and the seats are not in there. Not in the electrical diagrams and no mention anywhere in the manual itself of heated seats.

The service manager said if its not in the manual they're not stock...so they didn't have a clue either. When I assured them that they are stock factory seats and we talked about it, they said that there has to be a fuse because its a fire hazard and the current is higher than other circuits. They also said that because the current is high, the fuse will likely be in the engine compartment, but that it may be in the console near the switches.

Vanished, have you taken the console apart yet? So you know if there's a fuse or resistor in the circuit there? I think since my switches both fail to light up when switched it pretty well has to be a fuse or broken circuit of some kind. I plan to search tomorrow.

[ElectricEnergy]

Actually, SEs were also available in Black and Laguna Blue, but they were less common. I have a Black one.

My heated seats work, but barely. It seems like the heating elements probably wear out.

[wytbishop]

Ok, so I removed the console today to reveal the switches...and then my Multimeter crapped out instantly. I did get another one, but there was no more time to continue working. I searched the engine compartment and found no fuses other than the obvious main fuses. There is however a fuse in the kick panel inside the car for the "seat warmer", but it's in good shape. There is a control box of some kind under the passenger seat that I never noticed until today. Could someone enlighten me as to its purpose?

My plan is thus...

1) Ensure that there's power to the fuse in the kick panel. If there isn't then there must be a fuse blown somewhere prior to that point.

2) Assuming there is power to and from that fuse, check power to the switch.

3) Check the continuity of the switches themselves.

4) If there's power everywhere and the switches seem to be ok, the heating elements must be at fault.

If power isn't getting to the switches through the wiring harness...well then I guess I'd have to start tracing wires.

It's not very interesting I know, but it's late...and I have nothing better to do than type.

[umcamara]

Ok, so I removed the console today to reveal the switches...and then my Multimeter crapped out instantly. I did get another one, but there was no more time to continue working. I searched the engine compartment and found no fuses other than the obvious main fuses. There is however a fuse in the kick panel inside the car for the "seat warmer", but it's in good shape. There is a control box of some kind under the passenger seat that I never noticed until today. Could someone enlighten me as to its purpose?

My plan is thus...

1) Ensure that there's power to the fuse in the kick panel. If there isn't then there must be a fuse blown somewhere prior to that point.

2) Assuming there is power to and from that fuse, check power to the switch.

3) Check the continuity of the switches themselves.

4) If there's power everywhere and the switches seem to be ok, the heating elements must be at fault.

If power isn't getting to the switches through the wiring harness...well then I guess I'd have to start tracing wires.

It's not very interesting I know, but it's late...and I have nothing better to do than type.

Take that kick panel fuse out, and test it's continuity. Sometimes a fuse may appear fine, when in fact it's not.

[wytbishop]

OK. Here's what I've found.

Power goes to the fuse in the kick panel through the ignition switch...as expected. From there to the blue wire of each seat warmer switch. There are 2 bulbs int he switch, one which should illuminate with the interior lights and another which should illuminate when the warmer function is activated. Both bulbs in both of my switches are burnt out however, both switches do transmit 12V to the heating elements. The driver's seat heating element has continuity with about 14ohm resistance. This is the problem.

In any simple electrical circuit, the current through the load is equal to the voltage supplied divided by the resistance of the load. In order to produce heat, about 12A is required through the warming element (I estimate) but if the resistance of the element is 14ohm, the current through it will only be less than 1A because the supplied voltage is a constant 12V.

Burnt bulbs notwithstanding, my issue is with the heater elements. I figure resistance should be slightly less than 1ohm, which would produce a current through the element of a little less than the 15A fuse that is in the circuit.