So many projects, so little time

Topic: So many projects, so little time (Read 1861 times) previous topic - next topic

So many projects, so little time

September 20, 2009, 08:33:43 PM

I need to fix something on my alarm and want to upgrade it a little bit, but I also want to get this done before it gets cold:

The switches are the rear heated seat switches from a 1998 Jaguar XJ8, and I have a Town Car module on order (I chose that one because I have a 1995 Town Car EVTM). I chose these switches because they're small and have their own trim around the switch so mounting should be easy. Scoring heating pads for the seats might be tricky, but I'm just going to start with the driver's side for now. The seat foam is disintegrating from use and one of the vinyl panels is getting worn through. Right next to my mechanic's shop is a place that does auto upholstery (he did my headliner and rear deck felt), so I'll probably go to him with the pads and ask him to put them in while repairing the seat.

Tonight I want to see if I can prototype the circuit I'll need to have the switch drive the module. The switches are momentary pushbuttons, and the module expects an on/off switch. It shouldn't be hard to do.

Has anyone else considered something like this?

Edit: Hmm, it always helps when someone else has already figured it out: http://uk.geocities.com/ronj_1217/tg1s.html

So many projects, so little time

Reply #1 – September 20, 2009, 10:32:36 PM

Looks pretty interesting. You'll have to post up some pics once you're done, or at least close to done....

So many projects, so little time

Reply #2 – September 29, 2009, 11:50:39 PM

I'm slowly getting all the pieces I need. I have one seat heating element and a heating module. I need to look in the shed to see if I have a connector that will work. I first want to test what I have before getting the seat-back heating element. I'm going to have to build a board to handle the switches, but I already have it prototyped on a breadboard. When the components I ordered from SparkFun come in I'll build the real thing.

In other news: it looks like we're in for a hard winter in the northeast. I need to get cracking on this thing.

http://www.bloomberg.com/apps/news?pid=20601087&sid=amm7GJfWypJE

So many projects, so little time

Reply #3 – October 22, 2009, 04:11:09 PM

Well, I'm *trying* to get this project going, but I just can't catch a break. The only way I could get my hands on the heated seat module harness was to buy an entire seat track. It's listed as "COMES WITH EVERYTHING IN PICTURES ,AS PICTURED.", and shows the module and harness. I get the seat track, and...no module, and no connector. Everything *except* the module and connector are here.

NOT HAPPY.

So many projects, so little time

Reply #4 – October 27, 2009, 11:07:54 PM

Making some progress...

I'm still waiting on the connector to the heated seats module (I called the guy and he said he'd send it). In the meantime I'm building everything else for the project. I'm using 1998-2002 Ford radio connectors because they're easy to get, and using a SparkFun project board and case. The switches are wired up, and the clear box converts the momentary pushbuttons to the on/off signal the heated seats module(s) need. It also has 680-ohm resistors wired in for a hard-wired heat setting (corresponds to maybe 2.8 or so on the Lincoln's 1-5 setting dial). I'm going to power the module itself with relays, and that's where the Taurus relay module comes in.

I still have to test-fit everything to figure out exactly where everything will go. The clear box should definitely fit under the center console, but I'm not sure about the relays. It would be nice if both fit. If not, I'm sure I can come up with something, but somewhere under the console would be easiest.

At any rate this will all have to wait for a week and a half or so. I just found out that I have to go to Dayton in the middle of next week for work. I hate going through the hassle of flying so I'm opting to drive (ROAD TRIP!!!) Yes, I'm taking the 'Bird :D It's a lot more comfortable on long trips than the Explorer. Tomorrow it's getting plugs, an oil change, and a new starter solenoid.

I'm still anxious about the module connector. If anyone is planning any JY runs, PLEASE, PLEASE, PLEASE, if you spot a Town Car, snag one (or two) for me!

So many projects, so little time

Reply #5 – October 28, 2009, 09:28:33 PM

This is a good thread - show us how you place the heating pads. I may have to do something like this in additional to all my other planned interior mods. Unlike mine, this one is actually useful :p

So many projects, so little time

Reply #6 – October 31, 2009, 10:29:32 PM

A little update...the relay block is NOT necessary if you're using heating modules like I have (1995-199x Lincoln Town Car). They have built-in relays, so all you have to do is give it +12V to trigger it. You can also leave the temp control resistor connected all the time because that circuit is driven by the module's relay. I modded my board in the pic above to also output +12V when active as a result (there are two more wires coming out of it, using the two unused pin positions you see at the corners). Before, it was only connecting ground when active, which would drive an external relay and the LED in the switches. It meant adding two PNP transistors, but that's it. When everything is completed, I'll post the schematic for my board. It doesn't do much, it's basically a dual flip-flop that lets me use momentary push buttons instead of the slider switch that the heating module expects.

The heating pads are 02-03 Explorer pads, which are readily available new on eBay. They have the same pinout and plug as the Lincoln harness. Whether the temperature sensors match is something I'll find out when I test it.

My box will have to get power from a hot-in-run circuit, which shouldn't be hard to get. The heating modules themselves get a hot-at-all-times power source. The Lincoln uses a separate 30A fused circuit coming directly from the engine bay fuse block, and the T-Bird EVTM says to pull it from the 20A fused power that runs the power seats. I'll just do it the T-Bird way for now since I'm only going to get the driver's side done before winter. Next year I'll see about doing something more robust.

So many projects, so little time

Reply #7 – October 31, 2009, 11:13:01 PM

Here's the board schematic as it stands today. I doubt it will change, but you never know until I test it...

So many projects, so little time

Reply #8 – November 01, 2009, 12:37:38 PM

I can't wait until I can start doing a lot of things like this, once I have a garage to do it in (hopefully not too far off now). Dash, seat, and center console modifications will help bring this car up to today's standards for creature comforts (besides the parking brake pedal). I will have to steal this idea right before I reupholster the seats :p I plan on switching over to electronic climate controls (with servos to keep it all functional) and ditching the rest of the center dash to get rid of the 80's look that is still so prevalent everywhere. Sure some people claim to like it but it IS everywhere in many cars on the road and it sucks - there is no reason to keep this stuff stock in my mind.

Where are you planning on mounting the switches? Any other plans for interior mods? I'm looking for all the ideas I can get without messing with the dash pad itself.

So many projects, so little time

Reply #9 – November 01, 2009, 09:42:36 PM

Lol, you don't need no stinkin' garage :D Our garage is full of my dad's junk.

Just kidding of course! I'd kill for a garage to work in. It's going to get too cold to work on the T-Bird much longer, so I'm hurrying to get this done.

I've attached a picture that shows where I'm considering putting the switches, in order of preference. I won't really know what's possible until I go out there with a switch and do some checking.

So many projects, so little time

Reply #10 – November 01, 2009, 10:14:26 PM

I went outside and did some quick checking. #1 and #3 are borderline iffy. I didn't check #2, and #4 will always work though I might need to make another faceplate to move the voltmeter up a little. Another spot that might actually be the best place for the switches is on either side of the small ashtray. There's just enough room for the switches and that area should have the best structural strength.

So many projects, so little time

Reply #11 – November 01, 2009, 11:38:45 PM

I've done modifications in a garage at one point in time - I have no reason to do anything outside anymore but maintenance work. The things it doesn't need can wait until they can be done indoors, with a space heater.

So many projects, so little time

Reply #12 – November 02, 2009, 01:10:01 AM

Are you a smoker?

I would pull the lighter/ashtray panel, make a new face for it, then install the switches there.

So many projects, so little time

Reply #13 – November 02, 2009, 08:32:01 PM

Interesting idea. I don't smoke, but I have the cigarette lighter in the ashtray most of the time (I have an 11W solar cell on my rear deck that I keep plugged in). I have a few coins in change in there too, but I also have a small coin holder in the console. Maybe I'll see if I can remove the ashtray lid without breaking anything.

So many projects, so little time

Reply #14 – November 14, 2009, 08:02:59 PM

Almost there...

Here's a pic of my Explorer heated seat pads. I got everything working electrically, but one wrinkle was that the Town Car module apparently expects a higher resistance from the temperature sensors. The low resistance from the Explorer pads was making the module think the pads were already hot, so they wouldn't heat up.

Luckily I have an extra seat module, so I was able to do some bench testing with some LED's and a variable resistor. The LED would stand in for power to the pad, and the resistor would stand in for the temp sensor. I found that I had to add about 3500 ohms to make it behave properly. So, each pad has a little board inline with it, where there are four resistors in series: three 1k resistors and one 470-ohm resistor. I tried a pin from a 2003 Ford radio connector to act as a substitute pin, and it's a near-prefect match. These neat little cases came today from SparkFun, and they're a perfect fit over the boards.

I've already tested one pad, and tomorrow I plan to test both and mount the switches (they're already in the car--I did all the electrical work last weekend). I'm going to follow DVP's plan and put them in the ashtray area, for now at least.