This car does not have a disabler security system = your issue needs further diagnosis.

Here is the thread you need to study + the titles to review for correct diagnosis.

Fuel Injection
http://www.peachparts.com/shopforum/showthread.php?t=142406


Mercedes-Benz Driveability
Evaluating Electronic Engine Controls
by Steve Brotherton, Import Specialist
Published in: ImportCar∞, February 2001

Testing OVP

Help!! Need OVP plug schematic! "Over Voltage Protection relay"

Bizzarro OVP problem solved! "Over Voltage Protection relay"

This Volvo club page has a good overview of K-Jetronic Fuel Injection

Bosch D-Jetronic electronic fuel injection system

D-Jetronic History and Fundamentals

Jetronic

Bosch Fuel Injection and Engine Management

Bosch D Jetronic and K Jetronic Troubleshooting




Have a great day.

__________________
ASE Master Mechanic

Prototype R&D/testing:
Thermal & Aerodynamic System Engineering (TASE) Senior vehicle instrumentation technician.
Noise Vibration and Harshness (NVH).
Dynamometer.
Heat exchanger durability.
HV-A/C Climate Control.
Vehicle build.
Fleet Durability
Technical Quality Auditor.
Automotive Technical Writer

1985 300SD
1983 300D

https://www.boldegoist.com/