I built a breakout box for D-Jetronic systems to view signals coming to and from the ECU in static or running conditions. My first attempt at the engine harness to breakout box fixture was too fragile to use and resulted in a broken receiver guide. If you look at the ECU card edge receiver, you will see a plastic guide that the engine harness 25 pin connector slides into. That plastic piece locates the connector correctly onto the card edge of the ECU. I desoldered a card edge receiver from an old Saab D-jet ECU; another one from a burnt MB 116 ECU to make this interface.
I recently made some sawdust, router dust and sandpaper dust with some curly maple 4/4 stock I had on hand to build this receiver block to connect with my engine harness. I took the opportunity to improve the wire jacket with the same product MBGraham found at wirecare.com. The result is a more solid interface with the plastic receiver guide glued to a router channel in the maple. I also improved the wire connections by using the same tiny butt splices I use in my engine harness rebuilds. I crimped one end to the wire and filled the other end with solder (like the solder wells in the pins on every connector in the MB electrical system) I used a short length of foam weatherstrip to prevent interference and damage to the pins.
The result is a more rugged test kit for D-Jet systems. Still need to add a pickup for terminal 25 to read the ECU driver output. I am searching for a brass D-Jet emblem to dress it up a bit.
This breakout box helps identify where problems lie in an inoperative D-Jet system. My goal is to correlate Pertronix signals to pulse generator signals and possibly come up with a replacement signal generator in lieu of the PG. A signal generator can be adjusted to correct timing and duty cycle - tune the pulse created by Hall effect pickup eliminating the worn points problems of our pulse generators. It's just an idea at this point.
Last picture shows PG output - 5V square waves on a simple phase shift. Arduino or Raspberry kits can prolly handle that.
I recently made some sawdust, router dust and sandpaper dust with some curly maple 4/4 stock I had on hand to build this receiver block to connect with my engine harness. I took the opportunity to improve the wire jacket with the same product MBGraham found at wirecare.com. The result is a more solid interface with the plastic receiver guide glued to a router channel in the maple. I also improved the wire connections by using the same tiny butt splices I use in my engine harness rebuilds. I crimped one end to the wire and filled the other end with solder (like the solder wells in the pins on every connector in the MB electrical system) I used a short length of foam weatherstrip to prevent interference and damage to the pins.
The result is a more rugged test kit for D-Jet systems. Still need to add a pickup for terminal 25 to read the ECU driver output. I am searching for a brass D-Jet emblem to dress it up a bit.
This breakout box helps identify where problems lie in an inoperative D-Jet system. My goal is to correlate Pertronix signals to pulse generator signals and possibly come up with a replacement signal generator in lieu of the PG. A signal generator can be adjusted to correct timing and duty cycle - tune the pulse created by Hall effect pickup eliminating the worn points problems of our pulse generators. It's just an idea at this point.
Last picture shows PG output - 5V square waves on a simple phase shift. Arduino or Raspberry kits can prolly handle that.