ZF4 HP18 gear selector & kickdown cable operation

Links to removing the governor valve unit on the same transmission can be found here;
Part 1 • How to replace ZF- 4HP...
Part 2 • How to replace ZF4-HP1...
Part 3 • How to replace ZF4-HP1...
See how the kickdown & gear selector operates on a ZF4HP18.
Video shows how the kickdown cable 'cam' and the gear selector mechanism operates the various valves on the valve-block.
It also shows how the 'P' or 'PARK' position works on this automatic transmission. Other makes are similar.
Since this transmission is used in many makes of car such as Peugeot, Citroen, Alfa Romeo and Saab in either front-wheel drive and rear-wheel drive application, it's important to know the correct setting position of the gear selector BEFORE removing the valve block which incidentally is on top of the transmission in front-wheel drive cars (and underneath in rear-wheel drive cars)
With gear selector in FIRST, the toothed quadrant and the locating pin should be towards the front of the car as viewed when looking under the bonnet (hood) at the engine i.e Citroen XM, Peugeot 406, Alfa Romeo 164, Saab 9,5, etc. In this position, the gear selector valve with the cutout locates on the quadrant 'pin' since the valve will be fully home in the valve block. If this isn't done, it's next to impossible to align up the quadrant wheel with the selector valve as it tends to flop forward when positioning the valve block - so keep it in first before any strip down.
You see in the video how the kickdown cable actuates a 'cam wheel' or eccentric which in turn pushes on a roller ended valve on the underside of the valve block. Technically on the diesel engined cars it isn't really a kickdown cable but more a pressure sensor & actuating servo mechanism to allow the transmission to 'sense' the engine is under load such as accelerating. As the driver plants the throttle, the cable pulls and the cam wheel pushes on a valve which causes various events to take place such as the band-brake to tighten thus prevent slippage so car accelerates. That's a simplied description of the process. As four speed automatic transmissions go, the ZF4HP18 is fairly simple since it's all hydraulic and mechanical control. There are no electro-valves or ECU's on the actual transmission but it does have a shed-load of tiny parts and springs.
Apologies for shaky camera and flickering light. My normal filming camera and light was in use elsewhere so I had to use my garage LED inspection lamp - hence the flickering.
Links to removing the governor valve unit on the same transmission.
Part 1 • How to replace ZF- 4HP...
Part 2 • How to replace ZF4-HP1...
Part 3 • How to replace ZF4-HP1...