Solved heater problem 84 300D W123

SYMPTOMS:
- full heat all the time when temp dial anywhere but "MIN"
- heat coming from monovalve receiving no voltage
- full cold when in MIN detent / monovalve receiving voltage

SOLUTION:
Part number 0008221003 - the mystery box (on the W123, pull the glove box out and it's mounted above, ez to get to, one wiring harness plug and one screw)

- Junkyard pulls are all over ebay starting around $50.
- brinsonco.com has them for $115 reman by not-Programa w/three year warranty

Be aware that when other components upstream from this unit go bad, the problem can cascade downstream and burn out this box. These include the monovalve and the electric coolant boost pump. I checked my monovalve for resistance and it was 17, which was within the 11 to 19 acceptable range. I forget what the boost pump range is because I didn't check it...I put a new one on the car. ebay $90.

Tomorrow, refrigerant.

Spending too much money on this car.

Jim

You and me both...

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1984 300SD Orient Red/ Palomino
1989 560SEC
2016 Mazda 6 6 speed manual
1995 Ford F-150 reg cab 4.9 5speed manual

That mysterious box 000 822 10 03, doing some searching, comes up as either a "Temperature regulator" or A/C blower control regulator".

My 85 has 2 boxes together behind the glove box.

Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

For sure, it's not both.

The blower control regulator is 000 822 11 03.

Is there a way to test this regulator with a multimeter before spending the $50?

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85 300CD Signal Red/Tan sold
83 300D Manganese Brown 109K
97 E420 Midnight Blue 197K sold
98 BMW 328i Vert White 100K, sold
95 BMW 525i White 125K, sold
93 BMW 525iT Red 193K, sold
95 E320 Green Wagon 125K, sold
94 E320 White 127K, sold
85 300SD 156K Grey (Annie), sold
84 300D Lapis Blue 170K (Judy), sold
99 ML 320 Black (lease), 1998 C230 White (lease)
00 Honda S2000 Red (lease)
86 Mercedes 300E (sold)
84 Porsche 911 Red (sold), 1965 Porsche 911 White (sold)

theres a couple up on the auction site right now for $25. search for the part number but separate out the groups xxx xxx xxxx

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1981 NA 300D 310k miles

Most junk yards sell relays or switches in the $2 to $5 range.

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1985 300D 198K sold
1982 300D 202K
1989 300E 125K
1992 940T

"If you dont have time to do it safely, you dont have time to do it"

"The democracy will cease to exist when you take away from those who are willing to work and give to those who would not."

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Auxiliary Water Pump W126 1985 300SD DIY
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ASE Master Mechanic
asemastermechanic@juno.com

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
1984 190D
2003 Volvo V70
2002 Honda Civic

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