has anyone found a logic schematic of the vanagon wiring,ecu

[pushkick]

yes i know the bently has a wiring diagram. but they dont have a topology layout or a logic schematic or a event diagram, or logic flow diagram. why wouldnt they have a sequence of events diagram. this is the most important thing in designing a embeded system or any control system. most current systems even have a state transition diagram (std) that lets you know where the program or error occurred. at least they could have documented what they have done. dosent seem like a true german engineering accomplishment.
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i see said the blind man to his deaf dog
i am going to quit smoking and drinking and die a healthy man. gotta laugh
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1990 vw automatic camper

[djkeev]

[Syncronicity]

[stevey88]

[randywebb]

no colored lines in the Bentley
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1986 2.1L Westy 2wd Auto Trans.

[Jake de Villiers]

[djkeev]

Ok, on a practical side there are helps online such as this for troubleshooting the fuel injection system.

http://www.cabby-info.com/Files/DigifantProTrainingManual.pdf

Search around, you'll find a lot more helpful diagnostic procedures for troubleshooting.

The body itself is pretty straightforward.

Dave
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Stop Dead Photo Links how to post photos

Ghia
http://www.thesamba.com/vw/forum/viewtopic.php?t=392473

Vanagon
http://www.thesamba.com/vw/forum/viewtopic.php?p=6315537#6315537

Beetle
https://www.thesamba.com/vw/forum/viewtopic.php?t=482968&highlight=74+super+vert

[kamzcab86]

[pushkick]

look at the time and detail they go into the engine and it internal components. they have trouble shooting flowcharts for oil pressure, engine analysis etc. exploded view assembly drawings that are great. their wiring diagrams are pretty good to, they show and tell location of terminals and connectors and fuses (most), they give wire colors. they dont show routing of wires and location of items relative to van. and they dont give a sequence of events or flow chart of operation or of start up. i guess i could drive from californa to maine without a road map or a compass. i could also walk. usually even on your refrigerator they give a control schematic but they dont give a wiring diagram. lets be serious if a competitor wanted to they would just back engineer the system(and most probably do). they would download the the assembly code and disassemble, trace the printed circuit board and look up the components. but as a end user it would be nice to have at least a logic flowchart. it would surely help the people who maintenance these vehicles and the enthusiast and the diy's.
_________________
i see said the blind man to his deaf dog
i am going to quit smoking and drinking and die a healthy man. gotta laugh
there is no deed to the planet earth
1990 vw automatic camper

[AdrianC]

I'm not really sure what you're after, tbh.

Apart from a generic idiot's guide like the one linked to for injection, what are you expecting to see in this logical flowchart? That injection one doesn't really add anything to even a basic understanding of injection systems - if you're after a primer on how vehicle electrics work, then I'm not sure that a particular car's manual is the right place for that. If you're au fait with the basics, then the wiring diagram is all that's needed.
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Adrian
Zookeeper of a miscellany of motoring silliness, from 0.75bhp to 9ft tall.
Living life on the road in an '88 2.1DJ Westfalia Club Joker Hightop.
www.WhereverTheRoadGoes.com

[randywebb]

a color wiring diagram is all I want - is there one? if so, where??
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1986 2.1L Westy 2wd Auto Trans.

[AdrianC]

[MsTaboo]

Here is some help on how to read the Bentley wiring diagrams.
http://www.bentleypublishers.com/images//tech/vw/vw.wiring.diagram.pdf

It's not much, but might help.
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Currently:
'90 Syncro Westy 3 knob w/Zetec

The information age has morphed into the age of disinformation and willful ignorance. Agnotology!
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Resist Kleptocratic Oligarchy (and Idiocracy)!

[pushkick]

the bently wiring diagrams all have wire color designation on each wire
on the diagram. example is Y id for yellow, BL for blue, Wh/Y is white with yellow stripe. they are all listed in nomenclature and each line on the wiring diagram has the wire size in metric and the color. i dont have a pic that i can show you, but i do have a file that i can send you that is a little easier to follow than the bently. there are color wiring diagrams on this forum under technical/wiring and then you have to pick the type.
_________________
i see said the blind man to his deaf dog
i am going to quit smoking and drinking and die a healthy man. gotta laugh
there is no deed to the planet earth
1990 vw automatic camper

[rubbachicken]

i though the OP was looking for a diagram of what's inside the ECU
i'd be interested in that diagram also
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lucy's BIG adventure

meet 'burni'

[70coupyel]

Are you asking for something like this?

This is for a Ghia.
I don't think there is a colored chart like this for our vans.
VW saved $$$ by not having color in the Bentley manual.
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[randywebb]

Yes, that is the type of diagram you want - then you don't have to look up the German code for each wire color.
_________________
1986 2.1L Westy 2wd Auto Trans.

[pushkick]

here is a typical bently wiring diagram

[/img]
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i see said the blind man to his deaf dog
i am going to quit smoking and drinking and die a healthy man. gotta laugh
there is no deed to the planet earth
1990 vw automatic camper

[Howesight]

I play with Toyotas and Audis as well my syncro. The "logic" charts in the Toyota (and Subaru, for that matter) factory service manuals do give you choices in a flow chart to diagnose engine and fuel injection problems. The last step in the flow chart is always "replace ECU". In a Japanese vehicle, that is a drastic solution and almost always unnecessary.

In a Vanagon, it is actually a fairly common problem for the ECU to be the problem. Do they "short out"? NO. Do they get software problems? NO. What they DO get is breaks in the printed circuit board that can cause odd running for a long time before the ECU finally won't allow the engine to run. But nothing in the manual (nor elsewhere) has any means to test the "bad" ECU except to try a known-good one.

The point of all this is that these Vanagon vehicles are now so old that almost all of the failure modes anticipated in the Bentley manual, (which assumes no ground problems, no corroded or oxidized wires, connectors), are the last thing that would cause the problem(s).

The closest thing to a "flow chart" is in the digifant and dijijet "Pro-training Manuals" which actually explain WHY you are doing most of the checks and tests set out in the Bentley.

VW and Bentley never really published any knowledge base they may have accumulated (except for TSB's and who knows how to find them?) about which systems, sensors and parts failed most frequently. People here on the Samba can generally give a good account of those items.

Here are my pearls of wisdom:

Stuff that fails frequently and is/are cheap to simply replace rather than test:
- Temp 2 sensor;
- spark plug wires;
- distributor cap;
- rotor;
- thermostat;
- oil pressure sensor (only if that damn buzzer won't stop)
- note that unless the engine has an oil control problem, spark plugs in the WBX engines last a LONG time. But if you're replacing the plug wires, replace the spark plugs.

Wires/connections that frequently cause problems:

- main ground strap to driver side cylinder head;
- all ground wires in the engine compartment (clean the attachments points and check for corrosion in the wire end(s);
- Oxygen sensor co-axial wire (only if you can't get the oxy sensor system to behave as per normal);
- wiring to the Hall sender on the distributor: it gets kinked and dodgy in some instances.

Emissions test failures:
- FIRST, eliminate vacuum leaks (vacuum hoses, intake manifold elbow seals, Crankcase ventilation, valve cover gasket)
-adjust/replace throttle position switch;
- replace oxy sensor;
- replace catalytic converter;


Stuff that is almost always NOT the cause of poor running:

- Fuel injectors: even with a ton of gunk on injector tips, the engine will still run, but idle speed emissions get poor. Injectors are cheap to clean. They almost never fail.

- Fuel pressure regulator (if it fails, the diaphragm leaks fuel into the intake manifold and a grossly rich fuel mixture results).


Odd Stuff:
- ignition coils can fail after 20 years without complaint;
- Bad/old gasoline causes intake valves to stick open (due to varnish forming in old gasoline) with very weird running characteristics;
- Cat converter core can break, and plug and unplug the exhaust, again with variable running problems.
- the clamp that holds the distributor down can get bent to the point that it will not hold the distributor seated in the drive slot on the distributor drive. Easily solved by bending the hold-down portion.

The Vanagon engine control system is not a sophisticated bit of kit. The same problems tend to occur over and over. It's not rocket surgery, but you do need to sharpen your scalpel before cutting into the rocket.
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'86 Syncro Westy SVX