Hours of Operation: Mon - Fri 8:00am - 8:00pm

Welcome to Shoebox Electronix

Modern Electronic Products for Vintage VW Vanagons

Providing reliable, fair priced quality products to VW owners since 2003.






8691 Mini Monitor

Our flagship ECU Monitor in a new extra compact 4"x3" design

  • Push Button Input Select
  • Easily Dash Mounted
  • No Battery Required

8691 Pro ECU Monitor

New expanded capabilities for the professional repair facility

  • Data Logger Function
  • Mini panel mounted O-Scope
  • Analog & Digital Meters

Solar Panel Project

We are currently researching the technical aspects of integrating solar panels, solar panel controllers &  marine style 12V Batteries.

About us...

We started Shoebox Electronix in 2003 in Capitola California, and have worked closely with Peter Jones at the Van Cafe (originally Volks Cafe) from that time until his "retirement" in 2018. Our first product, now several times updated and refined, was the 8691 ECU Monitor. This product gave 1986-1981 Vanagon owners the ability to monitor ECU (Engine Control Unit) sensor inputs and signal outputs in either static (parked) or dynamic (driving) conditions. 

A second iteration, the 8385 model was added in 2006 to provide the same capability to 1983 - 1985 models.

In 2008, we added the 8491 Battery Saver, warning drivers they had left their headlight switch ON, after shutting down the engine, thus preventing possible dead battery syndrome.

2013 brought yet another new product, our Hall TPS (Throttle Position Switch), which has become an extremely popular replacement for worn out or broken OEM mechanical microswitches. )

This year, 2021, we are planning to release a new generation of ECU Monitor, the 8691 PRO. This versatile troubleshooting tool will be at home in the professional VW repair shop as well as in the individual Vanagon owner's garage. Added to the standard 8691 functionality are an Analog Meter, Three BNC Connectors for scope monitoring of ignition pulse signals, Digital Battery Level & Condition Meter, Push-Button Input Selection for digital and Analog Meters (you will be able to monitor two signals at the same time), Data Logging capability (in conjunction with user provided laptop), and (planned) miniature 2x3" Oscilloscope Display that can be utilized to observe signals graphically.

Prototype circuitry, enclosures and components  are currently being tested and evaluated, and we would like to have this product ready for sale by the middle of this year.

We are currently finalizing the circuit board design of the 8691 mini, and hope to have initial testing completed by March. At that time, we will have an initial production run of 100 circuit boards manufactured, and hopefully start marketing by June.

We proudly stand behind all our products, and cover each and every one with our Lifetime warranty. If one of our products fail , return it for repair or  replacement at no charge (except shipping to us).

Back in the early days - Niece Katie circa 2007 helping out.


Thanks again for the much needed tool. After spending hours trying to perform the tests it can do in as little time as it takes to plug it in and turn the knob I can say it's the best bang for buck piece of mind I carry.

Winter W, Odessa TX

I would like at minimum two more Bat Savers... I think your design is the most elegant on the market...

Dan N, San Jose CA

I  just installed the Battery Saver Alarm. Great product. I love it.

Gary F, Grand Rapids MI

Thank you. I am very happy with the ECU Monitor. It's a powerful tool. Without this, it is like wandering in a dark labyrinth, replacing perfectly good parts. I could have saved a lot of money.

Larry L, Santa Clara CA

Very Happy with item. A+++ (Hall TPS Kit) eBay sale - Jan 20, 2020

Anthony M, Gresham OR

I'm happy with it. (8691 ECU Monitor) eBay sale -

Jan 17, 2020

Scott O, Choctaw OK

"Hi Jim: Thanks for everything, up and running and working well. Thank you!" MK, Menlo Park, CA

"Hey Jim, Thanks for the shout out. That helped me alot." HS, email Referral

"You've done more than stand behind your product. You took extra steps to rehabilitate my throttle body, and I really appreciate that. I love how Vanagon owners help other Vanagon owners. It's not easy keeping these relics rolling." MR, Piru, CA

"Thanks again for such a great product. This really helped trouble shoot some very difficult problems on my van." DHM, Van Cafe Rental Customer

"Thanks for your help." TD, Bend OR

"I have used your ecu monitor with success on my Vanagon (from Peter @ Vancafe), but now have a different application in mind". MH, Palo Alto, CA

"ECU replaced. Car is now running again. Thanks for the help!" MS Orby, Sweden

"Hi! Love the 8691 !! Super Simple - Perfect ! Helped me find out my Throttle Switch was not working. PS-This was a Xmas gift from my wife!" Dan S, San Jose, CA

"Thanks again, this device is so useful, and has really helped me troubleshoot two big fuel injection issues in my van. I plan to permanently install it." DM, Redwood City, CA

"I hope that the Digijet section on your website will grow up in the nearest future, because it's very helpful to me and many other guys from Poland with this engine. Thanks a lot!" PP, Torun, Poland

"Great product! If you forget to turn off the lights, it seems like the alarm sounds for only about 10 seconds or so- and then goes off. I think this is a fantastic design, because it serves to remind you, but doesn't drone on annoyingly." GD (Santa Cruz High Class of 1990)

"Thank you for the prompt reply, have a Merry Christmas and Happy New Year. Cheers!" TW Victoria, Australia

"Got the package the day after Christmas, but it was Christmas to me to have the "box"; popped it in and with new brain and Idle control module, the bus purred, thank you so much, the 8691 worked great and allowed easy tuning, and diagnosing."SS Amesbury MA

" Your kit is very complete, and the directions are easy to follow." QH UC Davis CA

"Just received your 8691 monitor. Nice job on the packaging and completness of the kit." DS Van Cafe Customer

"I really appreciate you getting back to me on my questions. It appears that you are open to contact (rare these days)." JL Vancouver WA

"I rented the ECU Monitor from the Van Cafe that you built - what a great tool! I'd like to build that unit right into a permanent location." RW Sacramento CA

"Thank you for all your help, it is much appreciated! TO Detroit MI

"The indicator lights are performing per the book...and there are now no starting issues with my Vanagon." JP Van Cafe Customer

"Thanks for keeping me up to date with your excellent progress, and let me know if there's anything I can do to help" ML Bristol UK

"Nice talking to you this afternoon about the Digifant ECU! Thanks Jim!" BK San Luis Obispo CA

"Thanks for making this kit (Battery Saver) - hope you sell a bunch of them. I don't know how many times I've walked back to my van to make sure I've turned my headlights off." SN Seattle WA

Thanks so much, Jim. I'll look forward to your work. It looks like you have made a significant contribution to the later models...maybe I'll get one of your kits when I get back to the states.
Thanks also for posting this info, Jim. It helped me get my old '84 up and running here in Italy." BM Naples,Italy

"I am currently renting one of your excellent diagnostic tools (ECU Monitor). It is working great!" MK Granville OH

"Just found your site,what can I say!!! I've been looking for this info for years!! Thank you so much." CG Email from UK

I bought the ECU Monitor in kit form. Easy to put together. I will keep an eye on it, and learn how to use it correctly." ZT Van Cafe Customer

I purchased your ECU Monitor and had no problem installing it." PN Carlsbad CA

"I received a rental ECU Monitor last Friday, and installed Saturday. Very cool unit. Definately worth the price." Van Cafe Customer

"Hello Jim, I got my ECU Monitor and have it hooked up. Was very easy to solder the wires - everything works. I think everyone that has a Waterboxer engine should have one!" WS Van Cafe Customer

"I used the tool to diagnose a TPS that was not working properly and could only be diagnosed while driving the van." MP - Vancouver BC

"Thank you for posting the manual." TF Anchorage AK

"Really had fun watching the voltages from MA to NJ today!" LT Bedford MA

"Can I buy extra pigtails to connect to the ECUs in my other vehicles?" DS Van Cafe Customer

"I really can't say enough about this Digifant Monitor. It is just really cool!" JP Talahassie FL

"Hi Jim, Thanks so much! Received the adapter kit and ECU today - works like a charm! I am sure it's worth double every penny. Got the payment sent off to you as well. Thanks again ! Winter W, Odessa TX

You can also inquire about the functionality and reliability of our products at the Van Cafe in Santa Cruz CA. 831-426-1244, Mon-Fri 9am-6pm PST


Call or email us with any questions you may have.

Shoebox Electronix


Shoebox Electronix