Chasing the Hapy Electrical Gremlins (part 4)

Before I begin, I hope we all have a 2021 that allows us to all forget just how bad 2020 was. That really capped off quite a decade. Anyway, with the new decade now in front of us, let's all work together on making our little worlds more friendly, livable and Hapy. On that, I spent way more hours than I could count over the last few weeks clowning on this wiring. I work slowly, so even when I have a huge block of time, meticulous work takes nearly forever. I got so carried away in fact, I missed my usual posting day this week, so this one is a little late. HNY!

 

Wiring Diagram

I have completed the wiring diagram. I mentioned in a comment on that last post that I had to start over because of differences between the Jetta and New Beetle of the same year. So goes. I now have a 12-page custom wiring diagram for this build. It includes things that I have not yet completed nor posted about (like a glow-plug light), but it does NOT include anything about the original bus. So, when working on something related to the TDI, we use this new one. When addressing something in the 50-year old transporter, we reference the Bentley. I expect that I will be making small modifications to the diagram based on what happens during the harness surgery. I figure that if the diagram isn't accurate, it really isn't very valuable.

 

Complete the Cut-Apart
When I last posted, I was in the process of cutting down the part of the wiring harness that ties into the fuse box and relays. I have worked on this area before. In retrospect, I maintain that leaving the engine harnesses that go to the ECU untouched is the right answer. I had looked at cutting them down too, and concluded that is playing with fire. Besides, just this one harness was quite a time consumer. This harness has the T10 plugs (white, black, orange, blue) and a T6 that in the NewBeetle's case is red, but on other cars it is brown. As I mentioned, this also has the fuse box, and relays. It also includes the dashpod, an OBD-II plug, an oval "T10" that is also black that lives in the engine compartment and there are a handful of little 2 or 3 pin plugs for the alternator, air conditioning and coolant level. It's really a random collection of things; making a decent custom harness from it is not all that easy. Anyway, my goal was to label-label-cut enough so I could remove the harness and thin it out. After the over-zealous cutting I mentioned in my last post, this was going to get much bigger. I got the last few of that "handful of little things" label-label-cut so I could bring the whole thing onto my kitchen table. I will get into the thinning in a future post (probably my next one).

Install Plan

Few things that go well happen purely accidentally. You have to make a plan. With the fuse box, relays and dashpod out of the way, I could re-assess the spare tire well which I'm now calling the "wiring compartment". I need to keep the dashpod wired-in for the engine to run correctly. Since it is rather small, I planned for it to go into the far end of the compartment, with the rounded top slightly pitched so I can see it when I'm tinkering with the compartment exposed. On the other end, nearest the rear hatch, I planned to put the ECU, with the new fuse/relay box in between. For this to work, I'll need to shorten many wires in the harness I just removed, but the result will be a wiring compartment with a few cables, but no spaghetti. The T10's will plug into the thicker ECU harness below deck, so there will be some cleaning, arranging or obfuscating I'll need to do there.

Dashpod Mount

The donor pieces I received included the plastic surround for the New Beetle dash. The front/top cover snaps in place, hiding the screws that hold the dashpod to the plastic mount. This cover, however, makes the dashpod too wide to fit in the spare tire well, so I tossed it. I also had to cut down the plastic mount so it would fit, leaving the front-most flat section and the lower plastic bits that support the screw-holes for the dashpod. The second picture from the top shows the dashpod in 2 pieces. The upper 2 pieces were cut apart. I set and reset, fiddled with and eventually arrived at a spot for the dashpod. I marked holes, drilled them out and sent long screws thru the dashpod mount into the front curved side of the tire well. The dash pod clicked into place, and was quickly screwed into place. I checked clearance for the 2 cables that click into the dash pod, and there were no issues.

ECU (computer) Mount

Mounting the computer was not as simple. I received what looked like the plastic ECU holder back when I first got the New Beetle TDI, but I could not figure out how to orient the ECU so it would fit between the base and the protective flap door thing. So, I tossed the base, and screwed the flap door into the spare tire well instead. The ECU sits quite nicely on there and the cables are unimpeded. I will need to either Velcro the ECU to the mount or use something else. I will use short hook-end straps (like these) for now, since I have a few of them, so they are free. I intend to treat myself (and Hapy) to a Malone tune, eventually. I'll go Velcro after that, since I don't know how the Malone tune thing works with sending a computer in or if you get a flash download or what. Something to learn, and post about later, I guess.

Fuse / Relay Box Mount

final-ish look

With the ECU and dashpod located, there was really only just enough room for that fuse/relay box to fit between them as you can see from the picture on the side here. I chose to locate it on the inside of the wheel well, but it could just as easily gone on the other side. This way, the fuses are furthest from the rear hatch, but the orientation is consistent with my drawings (where I have the fuses at the top). This was a relatively simple matter of aligning the top of the closed fuse box with the top of the rear deck, marking the spots and boring them out. A standard hand drill doesn't fit there, so I put the drill bit in my Dremel. That is probably not the best solution, so I don't recommend it, but without one of those fancy 90* air-powered drill things, we make do with what we have.

 

That's it for today. Next time, I intend to get into the harness surgery. Thanks for following along and Hapy New Year-

Chasing the Hapy Electrical Gremlins (part 3)

Continuing on our journey through the darkness of the wiring rat's nest.

 

Shouldn't Have Cut That

not quite "before",
dashpod already pulled

I'll just jump right into the interesting part. Well, mostly. I started in the engine compartment and removed the wiring related to the coolant heater first: the relay box, the wires down to the glow plugs, etc. That much was great. Then, I moved on to looking at some of the wiring above, and as the bold-faced line implies, I cut something I would best not have.

 

Reflect back to the last time I clowned around on this wiring, I dug deep into the fuse-box. I started by pulling the fuses for circuits Hap doesn't need. Circuit by circuit, I cut that unnecessary wiring by referencing fuse sockets where the fuses had been pulled. That plan worked great. Lots of extra wiring got removed, and the engine still ran. I still had the sporadic not-limp-mode, and the occasional Hapy-don't-wanna-start issues, but they both seemed improved. Well, this time around, I got into the fusebox and saw a few wires that did not appear to have a partner on the other side of the fuse. So, I figured I just missed them the first time, and cut them. Well, that was wrong. Their "missing partner" was actually a common-line always-hot (circuit 30 in VW-speak) that was kind of hidden from view. Well, I didn't see them anyway. The wires I cut are for powering "engine control" circuits, of course. So, kinda important. Ugh.

Fuse Box Smaller

don't actually need
any of these relays

Once I realized that the wires I cut were critical, I needed a new plan. A while back, I bought a small relay box thing off eBay that has 6 relay slots and 6 fuse sockets. Once it arrived, I looked at how many fuses were in the donor fuse box and how many sockets were in that smaller box and the math did not add up. That was all before I did the clear out I mentioned above. After that, I was down to 7 fuses, and one of them was for the OBDII plug that I don't actually use. So, I think the fuse socket numbers may work. As for the relays, I only need 2 of the donor relays: the infamous 109 (main power) and old 180 (glow plugs). All the other ones can go, which leaves me 4 slots for other things, like the "RUN" and "START" trigger relays I have connecting the ignition from the front to the electrical from the donor. Neat. I didn't mean to change the fuse box and the relay plastic holder thing, but when I cut those two engine control wires the die was cast.

Label, Label, Cut

smarter way to remove
extra wiring

So, into the darkness we go. I started with the more obvious wires, like the thin little wires on the 180 (glow plug) relay. Then, I moved on to the T10 plugs. There are 5 (Blue, White, Black, Orange and Brown) 10-pin plugs in the mix of all that rat-nest. I unplugged them, and started dissecting by labeling either side of the cut, describing what is on the other side, and cutting. This picture on the right here explains the wire coming from the ignition switch position 86s as an example of how I dealt wit the wire-snarl.

While that sounds like quick work, I have moved slowly, researching each wire first, to make sure I don't have another "engine control" mishap. And, I want to do more than just label where it went; I want to know what it does first. This is a lot like a jigsaw puzzle where the more you do, the faster it goes until you eventually have all of the wires you intend to cut labelled and cut apart. I am almost done, which means the next post on wiring should include some building back up.

Diagramming

One last thing I have been doing, is crafting my own wiring diagram. I started by scanned the wiring diagram for the early ALH engine (80-pin ECU) from the Bentley. There are 13 pages. I am examining each circuit across the diagram and editing the image of the page to reflect what my circuitry will look like. I am retaining the original circuit numbering, etc. but adding the number of the fuse that I am using in the new fuse box to the documentation. Perhaps more importantly, I am erasing the wire references to things that I no longer have, like the coolant warming glow-plug stuff. My thinking is that this way someone who knows the original wiring (looking at you, Justin) can understand the diagram just as well as I do. This diagram will replace the diagrams in the 3-ring binder, since the 2 sets in there are both for later ALH models, so they are informative, but not exactly 100% representative. Between the cold and the dark, the diagramming effort helps me feel like I am moving forward while also creating clarity around the work.

My CoViD-19 Plea

I take a 2 mile walk pretty much every day to shake off the cabin fever and to get some exercise. Every day, I see 20-30 people also out taking walks, riding bikes or taking a run as well. That's great except I can count on one hand the number of people I encounter with a mask on at all (even worn wrong). The other day, I counted 3 people out of 28. Seriously. Our tiny state is consistently seeing over 1200 new cases a day, which is alarming when you consider our "summer peak" was 430 cases a day. Please keep your masks on, its not a political statement, it's not a chin-strap and it doesn't work unless it covers your nose and mouth. It's to protect others from you, not the other way around. We don't know if you have the virus or not, and quite frankly, if you're wandering around without a mask, and hanging around with others who don't have masks, then even if you had a test today... you don't know either. Just because you're outside doesn't mean you can run/walk/bike right past other people a-huffin and a-puffin (and sometimes a-coffin) without a mask. We are all tired of this, but that doesn't change anything about the importance of respecting it, and each other --

Hapy Heat Circle-Back

Brief post this week. I've been tearing down the electrical in the bus, and it's really not that photogenic. I'm not really sure how to post about it since it really is very boring from a read-all-about-it perspective. It does, however, take an incredible amount of time. I have spent probably 10 hours just slowly working through the circuits, figuring out what's what and then cutting and labeling things so I can put it all back together, but cleaner. So, while I figure out how to not bore people to tears, here's a quick update on the furnace.

Hapy outside townhouse
before Champoeg trip

As I post this, I am realizing that it was 10 years ago that my first marriage dissolved and, perhaps correspondingly, the TDI transplant really got legs. How time flies. Over the course of this next year, I will be hitting other 10-year milestones: getting my townhouse apartment (See Hey Strangers), that first camping trip with the boys to Champoeg State Park (See One Small Step for Van) in the TDI-powered bus, and meeting Boo (See Football, Friends and Further). Funny how 10 years later, we are still making improvements on Hapy, I am still fiddling with the TDI electrical and his exterior doesn't look much better. Where were we? Oh yeah, furnace fun.

 

Yeah Yeah, Follow the Manufacturer's Instructions

It's been a few months since I did the parking heater / camping heater install. As directed by the manufacturer, I have been turning the heater on and letting it run through it's cycles about every 6 weeks since. My last runs have been these last 2 weekends. 2 weeks ago, it was super cold (low 40*F's or ~5*C), so I thought it would be interesting to see how the heater sorted itself out. The heater had the interior of the bus genuinely warm in about 10 minutes.

 

Can't Leave Well Enough Alone

I thought I would experiment with the fuel pump frequency at the low end of the maintain cycle. This is the speed at which the heater would run when you achieved the target temperature. I figured that even at the recommended 1.3, the noise coming through could be disruptive when you're sleeping in the middle of nowhere. So, why not see if it can go super slow? So, I set it to 1, which is below the manufacturer's recommended low. I left the bus alone for a while to see if it could arrive at stasis. When I returned about an hour later, the inside of the bus was kind of exhausty-smelling. Yuck. I shut things down, and thought about whether I had an exhaust leak. I had not had that smell before, so either I hadn't run the tests long enough before, or maybe that manufacturer setting was related.

Not a Leak, Just a Bad Idea

Fast forward a week, and I'm ready to test again. This time, the temperature is just above freezing. I turned on the heater, using the built-in Afterburner WiFi, from my living room. This is so cool. So, I'm in my living room, and simply connect to the WiFi and go to 192.168.4.1 on a browser and bam, there's the controls for the heater. Tap on the thermostat image and a popup asks if you want to start the heater. Once that process started, I changed the fuel pump low setting back to 1.3. After about an hour, I checked the Afterburner browser on my phone. The heater was maintaining 68*F (20*C), and was in a maintain cycle running the fuel pump at 1.3. So, I put on my shoes and coat and went out to Hapy. No exhaust smell, just the smell of warm metal from the furnace. Of course it was totally comfy.

 

I now conclude that when you go below their recommendation, the heater still works, but I think the fan speed is somehow involved in the force at which the exhaust is expelled. Continuing this thought, since the fuel pump was set so low, the fan ran super slow, and the exhaust fumes built up inside the bus. Neat.

So, that's it for today. Basically, if you were wondering if you can run the heater at a setting below the manufacturer's recommendation, that answer is "yes", but the risk is not just premature wear. The greater, or at least more immediate, risk is that exhaust may not properly vent, so you could create an unsafe condition inside your bus. Thanks for following along-

Chasing the Hapy Electrical Gremlins (part 2)

Today continues where I left off with Hapy. Last, I had pulled a cable from the rear to the front, through small openings in the frame. I wired up the accelerator pedal plug into the new cable, as well as the ignition switch. Today, we take the next few steps.

Looking Up at 40F (4C)

Yes, it is still cold. It is December, after all. Now that Thanksgiving is behind us, the holiday music can come out in full force. Meanwhile, I'm dreaming of a not-rat's-nest wiring set up. Though, I suppose, a white Christmas would be pretty great too. We start with getting the wiring up front completely tidied up. I wrapped the exposed wires from the cable with 1/2" plastic wire wrap so it remains one cable almost all the way to the ignition switch. I split off the 6 wires for the accelerator pedal from the main bundle in front of the hand brake (front is front), and wrapped that in another plastic wrap. I ran that bundle behind the accelerator pedal support down to the pedal assembly. I then fed the excess cable down through the floor, leaving a little slack in the cable, but only just a little. The work in the cab is basically done for now.

Underneath

At this point, I slid under the front end and started sending cable back towards the rear. I was only able to get about midway before the original wire clump started to become a problem. See, I reused many of the same pass-throughs that I had used 10 years ago, and pushing the cable back against these wires was really not happening. So, recognizing that the old wires are no longer needed, I removed them. Unfortunately, they were taped to the 4-wire bundle for the brake switch, so I needed to remove that bundle as well. I wasn't using that circuit anyway: it only serves to notify the ECU that the brake has been pressed so turn off cruise control. I am obviously not using cruise control, so all of those wires go. I cleared wires all the way back to the spare-tire well, and confirmed the wire colors on the accelerator pedal circuit: they match. So, while the plug changed after the 1998 New Beetle TDI implementation, the wire colors didn't. Neat.

Lower Rat Nest Tear Down

Original outlet flange

Way back when I first did the swap, I had a Vanagon rear seat heater sitting on the accessory battery tray. That heater blocked from view how bad the wiring snarl was un the engine bay. Once the heater was removed this past Summer, it could have been obvious... if I'd looked. I did at this point in this rewire, and chose to start the cleanup right there. Hidden behind the heater were the relays and other associated wiring for the coolant glow plugs. For those not in-the-know, the manual transmission TDI's delivered with an aluminum coolant outlet flange. That flange had 3 glow plugs to warm the coolant. This flange was on this engine, but the coolant outlet sticks out the wrong side. In the bus, it sticks into the fuel tank. So, I swapped it out for the plastic coolant outlet flange that routes to the sides. Anyway, all that extra wiring and relay box were just sitting there. Were. They have been removed now. I moved a couple of ground wires that were in the middle of everything and then took all of the other wiring and pushed it up through the hole into the spare tire well. The cables that remain in the engine compartment are mostly against the compartment ceiling now. I didn't do much more, because I want the wiring up above to dictate how much more I do.

Research Again

It has been 10 years since I really looked at this wiring. Fortunately, TheSamba contributor AndyBees sent me a tome of wiring knowledge back then, and since I did not meaningfully stray from his work it will very much help me now. I barely scratched the surface of this documentation when I first did this install, though I did keep it in a 3-ring binder, with the other bus books in Hapy. 10 years ago, my goal was to just get it working and then I planned to circle-back and improve / clean it up. Well, after years of wrestling with the coolant (first leaks, then overheating) and then needing a break from the bus (hence, Oliver, the 1978 MGB), I'm only now getting to this. Based on a few hours of study, I expect I will be able to significantly reduce the remaining wiring. For example, I still have relays and wiring related to the radiator fan controls, even though I have those fans on a dashboard switch. And, of course, I will not be doing cruise control. There will be other discoveries as I go.

This is as far as I've gotten. My next steps are to start eliminating wiring related to functionality I am not going to retain (cruise control, etc). Since Hapy is outside/carported, this may take a while as I wait for nicer (read: warmer) days. We usually get a 50F/10C-degree day here and there. Since Hapy is blocking the garage bay where Oliver is parked, I may get my wrenching fix with some little projects on him when the weather is too cold to play with Hapy. Time, or more like weather, will tell. Thanks, as always for following along. Please stay isolated, and wear your mask / wash your hands when you can't.