MGB fuse box

While waiting for the box of parts to arrive from Moss, I wanted to look into the brake lights. They worked initially, but then stopped working after the test drive.

Check Your Fuses First
Since both brake lights went out at the same time, it wasn't a bulb, but it could be electrical. I started where I should always start: looking at the electrical diagram to see what the circuit does. If you thought the fuse box for the VW bus was simple with 12 fuses, the MGB fuse box will blow your mind. There are 4 fuses.

I'll pause while that sinks in.

4 fuses.

pic swiped from MGB forum

To be fair, there are 2 additional in-line fuses floating around near the box, but the box only has 4. The brake lights run through the same fuse as most of the rest of the car (the top, #1, fuse). This fuse also runs the wipers, lights, turn signals, etc. Some of those systems worked, but all of them were temperamental. I checked connectivity with my multi-meter, and the #1 fuse wasn't reading consistently through the box. One of the fuse-holders was flaky.

New Box
Swapping out a fuse box for a modern car is a huge undertaking. Even for a bus it could be a little tricky. Doing a 4-fuse box, however, was ridiculously easy. Circuit by circuit, I simply moved the old connections to the new box. the box sits on the passenger-side wheel arch and is held on with a couple sheet metal screws. A replacement is $8. Seriously. I paid many times that much for a used fusebox for the bus. While this did fix all the other systems, the brake lights still didn't work.

Brake Switch

how to test brakes on a roadster

After getting the fuse and fuse box to pass electrical signal, the brake lights still wouldn't light up. After checking the electrical diagram, I traced the electrical to the mechanical switch in the pedal box. The switch, like so many of the systems in the MGB, is extremely simple: a depress switch with 2 wires on it. It's basically an open door switch in your modern car: when the door is open, the little spring-loaded shaft extends, and the electrical connection is made / unmade. With the brake switch, it follows a similar principle, but unlike a door switch, the trigger sensitivity can be set. Around the outside of the trigger shaft is a threaded housing that is held in place with a thin nut. By varying the depth of the nut on the shaft, you can control how early or late in the travel of the pedal the brake light comes on. Neat. Seeing how this is a little car driving around in a world of really large SUV's and luxury sedans, having those lights fire as early as possible is the best idea. At this point, of course, I just want the to fire at all. So, I threaded the nut down so that moving the pedal less than an inch will fire the lights.

As you can see from the picture on the right here, I verified my various solutions by depressing the brake pedal with a roller pole. In the picture, you can see that I got the brake lights to work.

That's it for today. There continues to be a lot going on with the project. Multiple efforts are mid-progress, so there could be a delay in  posts while I finish one of them. As always, thanks for following along.

Thinking while Dinking

I unexpectedly had Sunday available to putter on the bus.  Boo was supposed to work, but suddenly didn't have a shift.  So, after a visit to the gym (I really need to do that more), I opened the garage door, turned on some tunes and pondered the bus.  Sometimes, you need to just be with your project to have an epiphany.  I had a flash of brilliance that (hopefully) could solve the wet-weather challenges for good.

Cutting Cards
I decided that a free afternoon shouldn't count in my build versus buy math since the afternoon was free.  So, I pulled out the Dremel and cut another door card.  Okay, back up.  First, I took the first door card I did and started trying to hang it on the passenger door.  I found little things that needed to get adjusted.  The grab handle holes weren't big enough.  Then the inner latch surround thing didn't fit.  Last, I realized that the holes for the door clips weren't there.  That was kinda fun, actually.  I took the ratty old door card and laid it on top of the new one.  I set those on top of a fresh piece of MDF.  Once lined up, I grabbed my drill with a 3/8" bit and bored straight through the door clip holes in the ratty door card into the new one and the MDF underneath.  Perfect.  I pulled the ratty card off the stack and traced the other holes and around the edge.  30 minutes with the Dremel later, I had a duplicate of the new card.

I still need to do a little sanding around the edges to make it a really nice fit.  The holes line up well and the grab handle, window winder and inner latch all mount correctly now.  Its just a little 100%-ing around the edges.

Hanging the Plastic Curtain
Originally, the early VW's had a "vapor barrier" between the door card and the steel door.  This was because no matter how good your seals were, water would seep inside the door, and could slowly rot the MDF/cardboard cards.  Most VW's have had these plastic sheets ripped out by stereo installers or confused mechanics, and their door cards have accordingly suffered.  I have tried a few different things over the years to get a plastic sheet to stay in place, but spray adhesives, contact cement and gorilla glue don't work.  Or they work too well.  Ultimately, I've just driven around without door cards while waiting for the answer to appear.  I found a posting on a website where a guy used that blue poster tack stuff (called BlueTac), and said it worked great.  I'll be trying it myself: a thin line of that sticky stuff all along the edge, taking care to avoid the door card mounting holes.  It occurred to me that this might be the solution I've been looking for with the belly pan too.

The belly pan, if you don't remember, is really a mechanical protection against rocks and such.  I've been trying to also use it as a splash-guard to keep the pedal electronics dry.  I'm going to try using the BlueTac solution with a sheet of plastic.  Figure, if I can protect a door card, I should be able to protect the electronics the same way: simple sheet of plastic held in-place with BlueTac.  I should also be able to cover the uppers, making the small sub-floor water-safe.  Neat.

That's it for today.  I bought some 3M-verson of BlueTac at Office Depot yesterday so I'll try the plastic thing this week.  Until then, here's another picture from the door card development effort.

3/8" drill bit fits perfectly in the mounting holes

Moving and Moving

Has it really been a month since I last posted?  Apparently so.  Its been a hectic March, so I apologize for the radio silence.  Its still crazy, so this will be brief, but should get you all caught up too.  Lots of work stuff has been going on, but I won't bore you with those details.  Let's just say I've been at work a lot.

Moving
First, my landlord chose to increase my rent by $80/month when my lease renew was up.  Seeing how my income is year-based, there's little I can do to bridge that gap other than cut spending elsewhere.  I'm already kinda near the bone spending-wise, so I decided to counter their proposal with a move-out.  This is where things get a little interesting.  I thought I had until the end of April, but it turns out the lease was through the 11th, so I had to get crackin' on finding another place to live, packing up stuff, and moving.  I have all that resolved temporarily, but I'm still vacating the old apartment.  In fact, I've used the bus for a large bulk of the transportation.

Water tight?
In my last post, I talked about getting the little clip on from the bottom to get the cooling system to seal.  That was the ticket, it turns out.  After multiple trips over the last week or so, he hasn't dripped a drop of water.  Oil, on the other hand, he continues to spread in little drips.  I'll solve that later.  Before I could really use the bus to help haul stuff, I had to make sure he was water-ready.  For those of you not in the US Pacific NorthWest, you may not know just how wet it is here right now.  We have had rain almost every day since my last post.  With standing and moving water on the streets, parking lots and just about everywhere else, I needed to be sure the bus could keep going if I hit some.

So, the weekend I gave notice, I slid under the bus and did some less-than-permanent adjustments to some wiring.  The radiator fan related wires all trigger off of a relay.  That relay is now wrapped in plastic wrap.  I know, that sounds positively awful, but it works, and the relay has stayed dry through this weather.

Next, I removed the belly pan from under the cab.  After a good cleaning, I covered the inside with vibration noise reducing sheets.  This should reduce a little road noise as well as seal off the small drain hole.  I then caulked the front and sides of the pan and re-attached it.  I know that if I hit a big enough puddle, water could come over the top of the support members, but that's a problem to be solved later too.  For now, I'll avoid large puddles at speed.  I didn't seal the back, thinking that any little bit of water that got in would need a way out.  So far, the caulk and hole patch work very well: electronic accelerator and brake pedal switch have been working perfectly.

And Moving
After the minor water-proofish modifications, the bus was ready.  I have driven him to and from a storage facility as well as to/from another apartment nearly every day for the last 2 weeks.  He has started right up, driven with pep and carried every burden I put inside without issue.  I have 2 or three large items left and then the usual debris that needs to be resolved, but my move is about complete.  The bus has been a great way to move in a steady downpour, keeping my stuff dry without tarps.

I need to figure out how I can park both my daily driver and the bus at the new place, though.  Unlike the old place, I don't have a 2-car garage.  So, I'll annoy my neighbors for a while as I resolve this.  As I mentioned earlier, this is a temporary housing solution, so I'll be moving again pretty soon.

That's it for today.  I've avoided my moving tasks for long enough this morning, and need to get back at it.  Today, I'll be completing the packing of the garage, and moving those big items I mentioned.  That will leave the final sweep for stuff, a trash run and then the final cleaning.  Moving is such fun...
 

Brake Switch, electrical research

This weekend was possibly the most beautiful 2-day weekend we've had in the Pacific NorthWest since the middle of last Fall. We had mostly clear skies with temps in the mid 60's on Saturday and into the low 70's on Sunday. It was perfect be-outside weather, so that's exactly how it was spent. Today, I'll talk about the brake switch installation I did on Saturday, and flap a bit about how the rest of the weekend was spent. Last, and certainly not least, my good friend from Kentucky (Andy) forwarded to me the net result of 9 months of researching circuits for the ALH TDI engine. Great stuff.

Brake Switch
In the bracket that holds the accelerator pedal to the VW NewBeetle, there is also a switch that is activated by the movement of the brake pedal. Recognizing that VW wouldn't put in a washer if they felt they could get away with it, we have to assume it has a purpose. It does, but not much of one for my implementation. First, the pedal switch turns off the cruise control. This is for safety, I believe. Second, the ECU (car computer) compares the signal from that switch with the other (and the brake lights) to see if there is a problem in the lighting. For my purpose, though, if there isn't a signal that acts like a brake switch, the ECU throws a code, and the check engine light pops on.

Fake it or Make it
There are 2 ways to handle the brake switch in a conversion. Many of the vanagon conversions have wired into the master cylinder switch and trigger the brake switch signal via a relay and a variable resistor to get the singal voltage right. I call this a "fake", but it seems to work very well for those that have done it. I actually got a switch from the donor car, so I figured I'd try fabricating a switch bracket and put it under the floor pan where the accelerator rheostat is. The picture to the right here shows where.

Clamp, Test, and Go
I took a short strip (less than 6 inches long, about an inch wide) or galvanized sheet steel that I had laying around from the radiator work. I got under the bus with the switch in hand and found a spot that allowed for the switch to open and close with the pedal motion when I held the switch against the lever. The switch button is activated / deactivated by pressing against the floor. I cut the mounting bit off of the old donor bracket, and pop-riveted it to the strip of steel. I then bend the strip of steel into an old-style capital "C" shape with little wings sticking out the end. I was able to get the clamp around the brake lever so the wings were about 3/8" apart. I removed it, drilled a couple of pilot holes, re-installed it and tightened the ends together with sheet metal screws. The clamp and the switch don't budge, and they will be covered by the same belly pan that will be covering the accelerator rheostat, so it should be weather-safe. Now, the switch opens and closes when the pedal is pressed and released - just like the donor car.

Present in the Mail
If you have followed my thread on the TDIClub, I have been anticipating a packet from one of the members there (AndyBees) containing the wiring diagram research he did for his vanagon TDI conversion project. His donor engine is from a 2002 Jetta, so much of the wiring is the same as my 1998 New Beetle donor. This significantly reduces the amount of time I will have to spend trying to figure things out. It doesn't completely eliminate my research though because there are some differences between these 2 configurations. For example, the 1998 New Beetle did not have an immobilizer, so I don't need to use the ignition key from my donor engine. Andy will have to. The circuit that deals with the starter is therefore different between our engines. And so it begins. I have barely started reading through his drawings and notes. I had some of the drawings in my Bentley for my Jetta, but his hand notes will prove to be very useful. Now, to find a wiring diagram for a 1998 New Beetle TDI without having to buy the $80 book.....

Weekend Fun
So, I did the brake switch over the course of a few hours Saturday afternoon. I spent the morning first at T's lacrosse game and the helping build raised garden beds at my kids' school. The evening was spent playing with C and reading Andy's notes. Sunday morning we skipped church to work in the yard. It was the first mow of the season, so there's the whole tune-up of the mower first. The grass looks terrible, but at least its shorter, and we were able to enjoy a picnic lunch on it. C had a lacrosse game too, so we all watched him play and then went out for ice cream. Overall, it was a great weekend with a great balance of volunteering, housework, kid time and a little project work on the old bus.

up next...
ALT belt, battery isolator, camping battery install, main battery install and, hopefully, wiring up the primary electrical (ALT-starter-battery).

pictures:
top - brake switch installed with the accelerator rheostat for positional clarity
bottom - close-up of the brake switch. Hard to tell how the action works. I'll take another one from more off the side so its more obvious.