1991 420SEL.
Attempting to bench adjust a new throttle valve switch using the FSM section 07.3-152 using a multimeter set to Ohms. I'm confused. It says to:
1. Ohmmeter: Set to measuring range 0= infiniity. Mine reads infinity as 1, and continuity as 000 or a beep when the leads are crossed.

2. Full load stop. Push the throttle valve to the full load stop. The display should be 0 ohms. Turn the throttle valve slightly in the direction of idle speed, the display should read infinity ohms. Mine stays at 1.

3. Idle speed stop: Push throttle valve to idle speed stop. Turn throttle valve switch until the display shows 0 ohms.
Lift throttle valve 0.2mm, the display should read infinity ohms.
This step was successful. Dialed it right in. However the Full load stop test does nothing. The meter never changed. Only pins 1 to 2 work. 2 to 3 does nothing over the test range for either Idle (closed) or Full Load (wide open). I did this test with the switch on the TV and with it off. Same results. Same results with the old switch. I replaced the switch just because it's a ***** to get at, and I was already in there to replace the donuts.
What if anything am I missing?

TIA Dave

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edit: after re-reading the original post I'm suspecting that you have pins (1 and 2) reversed in the connector. There are two switches and pin 2 is common to both. I believe that you have pin 2 in the pin 1 spot. That way one side will test right but the other will not. If this is off also make sure that you have 1 and 3 correct according to the diagram. Once you have pin 2 right you will be able to test 1 and 3 for proper orientation.

__________________

90 300TE 4-M
Turbo 103, T3/T04E 50 trim
T04B cover .60 AR
Stage 3 turbine .63 AR
A2W I/C, 40 LB/HR
MS2E, 60-2 Direct Coil Control
3" Exh, AEM W/B O2
Underdrive Alt. and P/S Pulleys,
Vented Rear Discs, .034 Booster.
3.07 diffs 1st Gear Start

90 300CE 104.980
Milled & ported head, 10.3:1 compression
197° intake cam w/20° advancer
Tuned CIS ECU
4° ignition advance
PCS TCM2000, built 722.6
600W networked suction fan
Sportline sway bars
V8 rear subframe, Quaife ATB 3.06 diff

Thanks for the feedback.
I'm doing this test with the TV on the bench. The TV switch only connects to the TV one way. On the other end of the switch wire the pins are maked 1 thru 3 with pin 2 being common. I tested the old and new switches both on and off the TV. The switch only moves about a quarter turn. Which is the total movement as the butterfly plate. With pins 1 and 2 connected I can set the Idle setting.
With the switch off the TV turned full counter clock wise or idle stop there is continuity. But, turned fully clock wise or full open the is no continuity with either 1 to 2 or 2 to 3 with either switch? I was interperting the FSM test to show continuity with the switch at both full open and full closed. And an open circuit in between.
This post was a sanity check to see if I was missing something or interperting the test wrong.
I'm still confused.
At full open and leads connected 1 to 3 I have continuity?

Thanks again. Dave

If you have continuity between 1 and 3 then 1 and 2 are swapped. I assume mislabeled as well.

__________________

90 300TE 4-M
Turbo 103, T3/T04E 50 trim
T04B cover .60 AR
Stage 3 turbine .63 AR
A2W I/C, 40 LB/HR
MS2E, 60-2 Direct Coil Control
3" Exh, AEM W/B O2
Underdrive Alt. and P/S Pulleys,
Vented Rear Discs, .034 Booster.
3.07 diffs 1st Gear Start

90 300CE 104.980
Milled & ported head, 10.3:1 compression
197° intake cam w/20° advancer
Tuned CIS ECU
4° ignition advance
PCS TCM2000, built 722.6
600W networked suction fan
Sportline sway bars
V8 rear subframe, Quaife ATB 3.06 diff

The original switch and the new switch are both MB parts and both test the same. Don't see how they could be mislabeled?
I"m thinkking the FSM is incorrect. The sketch is hosed up or something.