Adding Starcool on/off switch to dash

BrianW · 06-01-2012, 09:12 PM

Update 9-2014: the mod detailed in the thread below has been my #1 favorite thing I've added to my van, and still is working fine one year after it was done. It's a worthwhile update to anyone who has a pre-2000 SMB with Starcool and no remote on-off switch.

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My 98 Ford SMB EB has Starcool III, but does not seem to have the Starcool on/off switch that some folks have near the driver's side door. That seems like a handy thing to have, and I'd like to add one myself, but I'm not sure where to tap into the Starcool system to switch it. Thanks for any suggestions! (I did search the forums, but didn't see anything other that the mod to put the three-way switch in the dash, which is a great idea, but a bit beyond what I want to attempt.)

Scalf77 · 06-02-2012, 08:03 AM

Here is the relay panel for my 2004 Starcool III. I have outlined the sections in red that I believe would need to be added. The dashed green line is how I suspect it is wired today. Hope this helps

-greg

BrianW · 06-02-2012, 08:05 PM

Thanks for the schematic! Very helpful. I'll have to go in and eyeball how it's setup now. Looks like they added the switch option to the system in 2000, two years after my van.

Still interested in hearing from anyone who may have done this mod to their van already...

BrianW · 05-31-2013, 08:26 AM

As noted above, my 1998 Ford SMB with Starcool III lacked the remote on/off blower switch that became standard in 2000. It was a pain always having to go back and turn the blower fan on/off when starting out or parking. I coveted the remote switch those of you with the newer SMBs have. I finally got around to doing this mod last week, with many thanks to the schematic that Scalf77 posted of the newer Starcool III with remote switch.

Instead of adding it behind the driver's head, I decided to install a lighted switch on the dash HVAC panel, just under the blower speed switch. This is where the OEM rear AC blower switch would mount on vans so equipped. I figured it would a lot easier to access there, more tightly integrated with the whole "AC experience," and since it's a lighted switch I'll be less likely to forget to turn it off.

Even if you have the SMB-installed remote switch already, you may want to consider moving it to the dash position like I did. It would be a really easy mod, as you have the relay and whatnot already wired by SMB. You'd just have to run some wiring.

Scalf77 did a great write-up about adding a similar switch to the same area, but using a multi-speed control and several relays. It's a great idea, but I didn't want to get that involved. If you feel motivated, you can find his excellent thread here: viewtopic.php?f=13&t=3260

Here's a write up on what I did.

Tools and stuff you'll need:

1. Wire to reach from the Starcool relay panel to the dash. I used 16 gauge, since it's not carrying much load. Also, shorter pieces for the relay jumpers and dash power and ground wiring.
2. Wire connectors ring or spade connectors, and at least 7 insulated female push connectors (4 for the relay, 3 for the switch).
3. Wire stripper/crimper
4. Screwdrivers
5. Trim removal tool (or big flat screwdriver)

First, add a fifth relay to the Starcool relay panel (probably under your gaucho or dinette seat). See the schematic above for how to run it. Find the fuse for the blower (20 amp fuse) and pull it. Trace the wire from that fuse position to the relay distribution block (location #8 in the schematic). Disconnect the “downstream” wire (the wire that goes to the blower). Make up a small jumper cable to go from the distribution block to the new relay. It should have a spade or ring terminal on the end that goes into the block and a female push connector (insulated) for the end that goes into the relay.

Here’s where my install varies from the SMB schematic above: if you are installing a lighted switch, do NOT jump the two connectors on the relay (87 and 86). Just attach the wire from the distribution block to terminal 87 on the relay.

[If you are installing a NON-lighted switch, like SMB does, set it up like the schematic by jumping a wire from relay terminal 87 to 86. This is most easily done when you are making up the jumper cable from the distribution block -- crimp a second wire into the push connector end at the same time, and then add another push connector at the end of the second wire.]

Next, take the original wire you disconnected from the distribution block, cut off the SMB-installed spade connector and put a female push connector on it, and attach it to relay terminal #30. This is the wire that provides power to the blower. Finally, run a ground wire from relay terminal 86 to a suitable grounding position on the van body/frame/whatever (I found a bolt in the inverter compartment that connected to the frame and just tagged onto that).

BrianW · 05-31-2013, 08:29 AM

Now you need to wire the new dash switch into the relay. Run a wire from the relay up to the location where you are mounting the remote switch. Prepare for this by removing the necessary trim panels; I removed the driver-side door sill, loosened the kick panel near the parking brake, removed the panel under the steering wheel, loosened and popped-out the speedometer cluster panel, and pulled out the panel that the stereo/HVAC controls are mounted in. This is probably the most time-consuming part of the project if you want to do it right. I ran the wire behind my cabinets, under the driver-side door sill, up under the kick panel near the parking brake, and then into the dash area.

Prepare the wiring for the switch. For a lighted switch, you’ll need three wires: a 12V hot lead, preferably from someplace ignition switched (and fused); a ground wire; and the wire coming from the relay. Since you are only powering a small LED in the switch and the remote turn-on function of the relay, the hot wire won’t draw very much power. For a NON-lighted switch, you’ll only need a ground wire and the wire from the relay. Put female insulated push connectors on each wire.

With the HVAC panel apart, prepare the switch panel for the new switch. I find that the circular lighted switches are the easiest to mount because of their shape. Look on the back of the HVAC plate, and you’ll see a spot under the existing OEM blower multi-speed switch where a wiring harness is attached to a blind holder. I assume this is the wiring harness for the OEM rear AC setup, but it’s not used for anything on vans that don’t have that setup. (If you are really motivated, you could probably trace that to the back somehow and just use one of those wires instead of running a new one.) Pop that off and note the square bracket on the back of the white panel. Next, remove the black front part of the HVAC panel from the white backing plate (where all the wires go). The front fits in with press-fit tabs and is easy to remove.

On the white plate, trim some of the square bracket (the blind wiring harness holder mentioned above) to make room for the switch and wires, and also drill a hole there to run the wires through the white panel.

BrianW · 05-31-2013, 08:32 AM

Flip the black plate over and you’ll see there is a circular molded part where the OEM rear switch would go. This is where you will drill for your switch. Also note the clear plastic reinforcing on the back. Cut out an appropriate area of the clear plastic in the location where the new switch will go (I scored it with a utility knife and then broke it off with pliers). Using the OEM circular molded area as a guide, drill a bigger hole to fit your switch. I believe it is 15/16” for most of the common round rocker switches. I used a speed bit, since that’s all I had handy in that size. It worked ok, but messed up the front of the black panel a bit, unfortunately, as you can see in the photo since I drilled from the back. I thought it solid black plastic, but the front is actually a big sticker, which is why it tore a bit. Next time I'm at the junkyard I'll try to score a new faceplate.

With the white and black panels still separate, install the switch into the black plate.

Run wires through the white panel and attach them to the back of the switch. Lighted switches will have three connection points. One is for 12v hot, one is for “load,” and one for ground. The wire from the Starcool relay in the back goes to “load,” and the other two are obvious. Usually the “load” connection is in the center of the three tabs, but check your switch to make sure. Reinstall the 20 amp fuse you pulled at the start back in the Starcool relay panel area and test to make sure everything works (don’t forget to also turn the main blower multi-position switch on). If so, put everything back together and you are done!

Scalf77 · 05-31-2013, 03:25 PM

Nice job.

BrianW · 05-31-2013, 05:04 PM

Quote:

Originally Posted by Scalf77

Nice job.

Thanks! You made it possible by posting the schematic. I like your mod better, but I wasn't motivated enough to do all that extra wiring.