E9 D-Jetronic Injectors not Triggering

This shows the connection from the CSV relay terminal to the CSV's plug. 20250916_161135.jpg
Note that the CSV relay as shown on the left comes with an additional connector compared to the main control relay.20250920_101720.jpg
This is showing the diagram for the connection of thermal delay switch (160) to the cold start relay (169).20250920_104914.jpg
Make sure not to mix the connectin with the water temperature sensor.
20250920_104936.jpg
 
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Thanks to this community & SFDON's Lending Library/guidance, the engine started.

For some reason unplugging the CSV, allowed the ECU to trigger the injectors.

@TomHom
Thanks for the info/pics. Verified it is the 5 pronged CSV relay.
Verified connections @ Thermo switch and CSV by wire #.

#19 (30) to ECU verified grounded
#38 (87) to CSV verified grounded. Believe this is normal since its grounding through internals of the CSV?
#40 (85) coolant temp switch verified ground, not sure how this works, bimetallic?
#43 (86) coolant temp switch verified ground, not sure if this is the correct reading.
#44 (86c) to starter 50, verified 12v when starter activated.

Is it common for the diodes in the CSV to fail, could this possibly explain symptoms?

Thanks everyone!
 
Check your CSV:
20250921_140804.jpg
The resistance should be about 4 Ohm.
Check for short-circuit between each pin and the housing (ground).
Check the wiring between connector of CSV and pin 87 of the relay connector for continuity
20250921_140309.jpg
Do a short-circuit check on the wiring of both relays20250921_142503.jpg
First check on each connector between each pin, then check connector to connector between each pin.
Another nasty fault is the plug at the thermal-delay-switch being forced in place in the wrong direction
This can easily happen since the Bakelite housing may brake when trying to force in the plug.20250921_171158.jpg
You may check the diodes of your CSV relay by measuring the resistance. Applying positive on either connector 86c or 87 and minus to 86 should give you readings of about 1.2 kOhm. Reversing the polarity will give you infinite resistance.
 

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Hello Tom-

When he followed YOUR directions! By checking the relay base to the CSV for shorts and removing the CSV relay- the engine immediately started. Two days later he passed the final inspection deadline with 2 days to spare.
Happy shop and happy owner.
 
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