NO, there is no starter module.

My best guess would be:
* a bad ground, body to engine/transmission.
* a failing NSS = Neutral Safety Switch on the transmission.
* a failing ignition switch.


Broken Neutral Safety Switch and replacing shifter bushings
Broken Neutral Safety Switch and replacing shifter bushings - PeachParts Mercedes ShopForum

Replacing all shifter bushings on W126 - p.1
Replacing all shifter bushings on W126 - p.1 - PeachParts Mercedes ShopForum

Ignition Cylinder Tumbler replacement + Key issues; mixed diesel/gas
Ignition Cylinder Tumbler replacement; mixed diesel/gas - PeachParts Mercedes ShopForum



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