AC Programmer Manual Conversion or Vacuum Test Jumper

[Kneale Brownson]

Great report, Matthew.  Did you take any photos of the parts involved?

At 06:18 PM 08/21/2001 -0500, Matthew Caprio wrote:

>AC Programmer Manual Conversion or Vacuum Test Jumper
>
>Keywords:
>AC, programmer, solenoid valve, solenoid switch, vacuum switch, vents, 
>flaps, automatic climate control.
>
>Applies to:
>86-88 5000 (and maybe more models and years)
>
>Background:
>The solenoid vacuum valves in Audi AC Programmers control the flow of 
>vacuum to the AC vent actuators.  These solenoid valves have a tendency to 
>become clogged or contaminated by oil.  Bypassing these solenoid valves 
>can be useful as a diagnostic tool (to determine if the problem is lack of 
>vacuum, failed signals, or clogged valves), or as a long term solution to 
>convert the programmer to manual operation.
>
>Fix:
>A vacuum line jumper can be made from parts inside the programmer to route 
>the vacuum input source directly to the vacuum acutators, bypassing the 
>solenoid valves and all their electronics.  This jumper can be left inside 
>the existing programmer, or can be made with parts from a junked 
>programmer as a stand alone unit.
>
>How to make it:
>The jumper consists of 2 parts and some vacuum hose.  The parts are: 1.) 
>the connector block from the AC programmer where the 6 port vacuum 
>connection plugs in.  2.) the vacuum splitter block from the AC programmer 
>where the 1 vacuum input is split into 4 lines that normally feed the 4 
>solenoid valves.
>
>The ports on the connector block are numbered 1-6.  The ports on the 
>splitter block are numbered 1-6.  Run 4 lines from the connector block 
>ports 1,2,3,4 to the vacuum splitter block ports 3,4,5,6 (the order is not 
>important).  Run 1 line from the connector block port 5 to the splitter 
>block 2.  Cap off splitter block port 1 with the red rubber cap that 
>should already be on there.
>
>Secure all hoses in place with some sort of silicone or glue (nothing that 
>will be sucked in there and clog up anything).
>
>Plug this into the car's clear colored vacuum harness connector with the 
>colorful tubes.  You are ready to run.
>
>This arrangement forces the following conditions:
>-recirc door open (no outside air flowing into cabin)
>-heater valve closed (no hot coolant flowing into heater core for heat)
>-all air routed away from defrost
>-all air redirected fully through dash vents at the driver
>
>Notes:
>This arrangement is best for summer AC mode.
>All other normal programmer arrangements (defrost, bilevel, etc) can be 
>made manually with this jumper by disconnecting (AND CAPPING) the proper 
>line from the splitter block to the connector block.  Both ends must be 
>capped to prevent vacuum leaks and contamination of the vacuum 
>actuators.  Create your own exciting custom settings!  The following table 
>indicates what does what:
>
>Block Port Number - Harness Line Color - Function
>1 - red - shuts recirc door AND closes hot flow to heater core (with 
>vacuum applied)
>2 - yellow - reroutes air from footwell (default) to half center vents 
>bilevel (with vac)
>3 - green - reroutes air from footwell (default) to full center vents 
>(with vacuum applied)
>4 - blue - reroutes air from defrost (default) to footwell (with vacuum 
>applied)
>5 - black - input vacuum source
>6 - no connection - no function
>
>note that port 1 eventually splits to perform 2 functions- closing heater 
>valve and closing recirc door flap.
>
>Other notes:
>The splitter block also contains a check valve which prevents air from 
>flowing in the wrong direction.  Test this check valve before you make the 
>jumper to ensure you have a reliable one.  To test, supply a vacuum (or 
>suck with your mouth) on a hose to port 2 on the splitter block.  You 
>should be able to suck, but not blow if the check valve is working properly.
>
>Testing the system with the jumper:
>If the jumper is properly made and installed, and your system directs air 
>as indicated above, then you know that 1.) you have adequate vacuum coming 
>from your black hose and the "egg crate" accumulator.  2.) that your 
>actuators are working.  3.) there are no vacuum leaks in your colored 
>vacuum hoses going to your actuators.  Any problems that may exist are 
>either in 1.) AC head (generating the commands), 2.) the connections 
>between the head and the programmer, 3.) the programmer itself or a 
>solenoid valve.
>
>FYI: a commonly reported problem on these cars is that the return spring 
>breaks on the recirc door to leave it in recirc even with the heat on 
>(acting like the vacuum is applied to port 1, but opening the heater 
>valve).  Or, the bracket which supports the return spring cracks.  Another 
>one is that the hose to the recirc door sometimes falls off.  Oh yeah, 
>also there may be a spurious / weak voltage source to the programmer that 
>sometimes is not enough to actuate the solenoids-- this is real difficult 
>one to diagnose, but that's how I learned all of the above in the 
>process.  I'm sure there are more, since this system does NOT age well, 
>but I haven't heard them all.
>
>Good luck, and I hope the list can benefit from this hard learned info.
>Matthew Caprio
>Austin, TX
>88 5ksQ