Jump to content
  • When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.

id the relay


71bmr02

Recommended Posts

I was hoping to find a delay relay for the wipers to upgrade my system and came across this  on a wiring harness i have.  No numbers on it, all worn off likely from being in storage.  This doesnt appear to be the wiper delay relay, what is it?

 

Thanks

DSC02524.JPG.d5f99d659e2c45750769846d9f7bb102.JPG

 

DSC02525.JPG.582e2f674689881852c26689c1d68527.JPG

 

Gale H.

71 2002 daily driver

70 2002 malaga (pc)

83 320i (pc)

Link to comment
Share on other sites

On 3/23/2018 at 10:13 AM, Schnellvintage said:

The EGR check lights where activated mechanically off the speedo cable. If I remember, that looks like the relay for the magnetic vacuum switches off the smogged 02's.  I have been known to not remember everything correctly...:)

Matt

 

+1

 

I agree with Matt.  It’s a good ol' Drehzahlschalter (an engine speed relay), and it controls the magnetic vacuum switches on 1974 and later 2002’s.  It is part of the U.S. emissions system.  It is not found on tii’s, which have a similar looking, but different, Zeitschalter (a timed cold start relay).

 

Please don’t ask me any questions about how and when it works, as the above statement totally exhausted my knowledge of it...?

 

The last two photos show one in captivity, on my ‘76 in August 1983 and in February 2013.

 

Regards,

 

Steve

 

 

B3A634E9-39CA-43FC-AC79-3953AA0BEA36.jpeg

12EF137C-AE05-4ACD-8C7B-CC42715CD95F.jpeg

CC93EB4B-3704-4E2A-9E60-81675E8BEFAC.jpeg

CF83547D-18D0-49FD-82C1-61DAA63DE7E3.jpeg

Edited by Conserv

1976 2002 Polaris, 2742541 (original owner)

1973 2002tii Inka, 2762757 (not-the-original owner)

Link to comment
Share on other sites

Definitely not a wiper relay-all the ones I've seen have black plastic cases, and live under the dash, near the turn signal relay and the hood release latch.

 

The seven terminal wiper relay with the intermittent setting feature you seek will be found on '76 2002s, some '75s and all E21 320's.  On the '02s, look for a wiper lever that has three markings on the knob--a dashed line for intermittent, a single line for low speed and two lines for high speed.  

 

If you have a squarelight car, it'll be pre-wired for the intermittent feature; you just need the relay and the proper steering column wiper lever; if you have a roundie with a wiper relay, you'll need the proper dash switch that governs wiper speed (three positions vs two) and a wiring harness (pm me if you'd like the wiring diagram). The wiper switch on the stalk remains the same.  If you have an early roundie with no relay, you're better off finding a Hella universal intermittent relay kit.  

 

cheers

mike

'69 Nevada sunroof-Wolfgang-bought new
'73 Sahara sunroof-Ludwig-since '78
'91 Brillantrot 318is sunroof-Georg Friederich 
Fiat Topolini (Benito & Luigi), Renault 4CVs (Anatole, Lucky Pierre, Brigette) & Kermit, the Bugeye Sprite

Link to comment
Share on other sites

Thanks all.  consensus seems to be it's an engine speed control relay which makes it almost useless except as a wall hanger an I'm not so sure i'd want to take up that much wall space.   Unless someone wants to kick in another shot at this, we'll save the forum brainpower for something more important.

 

Thanks again

Gale H.

71 2002 daily driver

70 2002 malaga (pc)

83 320i (pc)

Link to comment
Share on other sites

"Drehzahlschalter" translates as "Speed Switch"... perhaps the Change Over Relay?  Sounds like a kick-down switch as you would find on an automatic tranny car.

 

 

image.thumb.png.686eccda7d02091499fbc32ed81a1737.png

1972 BMW Inka 2002Tii  ?

1974 BMW Turkis 3.0 CSi ?

1972 MBZ Weiss 280SE 4.5 

2006 BMW Cobalt 530i (38,700 m original)

Link to comment
Share on other sites

2 hours ago, Swiss 2002Tii said:

"Drehzahlschalter" translates as "Speed Switch"... perhaps the Change Over Relay?  Sounds like a kick-down switch as you would find on an automatic tranny car.

 

 

image.thumb.png.686eccda7d02091499fbc32ed81a1737.png

 

I suspect this is not a wiring diagram for 1974 through 1976 U.S.-spec cars, with full U.S. emissions controls.  I’m not absolutely certain one exists that includes the emissions system.  And I believe that 1974 through 1976 U.S.-spec cars are themselves not identical from an emissions control perspective, since all 1975 and California-only 1976 examples had thermal reactors.

 

The Drehzahlschalter is part of the emissions controls, which is what the electromagnetic vacuum valves also serve.  And it appeared originally on all 1974 through 1976 U.S.-spec 2002’s (not on 1974 tii’s). My ‘76, for instance, has a manual transmission, and was manufactured with a manual transmission.  I’ve shown photos above of the original Drehzahlschalter on my ‘76.  If you ditched the emissions system, you generally ditched this!

 

Just to be clear, I wasn’t speculating in my prior post that this might be part of the emissions system, after 42 years with my ‘76 — which retains  its fully-operational emissions controls — I am quite confident I know what a Drehzahlschalter relates to; I just don’t know when and how it “does its thing,” but it revolves around engine speed.

 

Regards,

 

Steve

 

Edited by Conserv

1976 2002 Polaris, 2742541 (original owner)

1973 2002tii Inka, 2762757 (not-the-original owner)

Link to comment
Share on other sites

Yep...it's the speed relay. 

The only function of this relay is to provide  +12V  to the WHITE electro-magnetic vacuum valve on the bulkhead.

This happens when the engine speed is 1650 +/- 50 rpm.  The +12V closes the WHITE valve, thus shutting off vacuum to the DASH POT, which  extends the rod to crack open the throttle.

This is useful when decelerating (throttle closed, high rpm) to reduce vacuum and high pressure in the engine (think blow-by from the valve cover).

If you don't have/use the Dash Pot, then toss the White valve and Speed Relay into the neighbor's pool.

 

5ab89364acfcc_BMWSpeedRelay.thumb.jpg.bf39e8d1635aabbcefa585092d8cfea3.jpg

 

  • Like 2
Link to comment
Share on other sites

4 hours ago, John76 said:

Yep...it's the speed relay. 

The only function of this relay is to provide  +12V  to the WHITE electro-magnetic vacuum valve on the bulkhead.

This happens when the engine speed is 1650 +/- 50 rpm.  The +12V closes the WHITE valve, thus shutting off vacuum to the DASH POT, which  extends the rod to crack open the throttle.

This is useful when decelerating (throttle closed, high rpm) to reduce vacuum and high pressure in the engine (think blow-by from the valve cover).

If you don't have/use the Dash Pot, then toss the White valve and Speed Relay into the neighbor's pool.

 

5ab89364acfcc_BMWSpeedRelay.thumb.jpg.bf39e8d1635aabbcefa585092d8cfea3.jpg

 

 

Thanks, John.

 

Very good to know, finally.... ?

 

Love the illustration!

 

Best regards,

 

Steve

 

Edited by Conserv

1976 2002 Polaris, 2742541 (original owner)

1973 2002tii Inka, 2762757 (not-the-original owner)

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • BMW Neue Klasse - a birth of a Sports Sedan

    BMW Neue Klasse - a birth of a Sports Sedan

    Unveiling of the Neue Klasse Unveiled in 1961, BMW 1500 sedan was a revolutionary concept at the outset of the '60s. No tail fins or chrome fountains. Instead, what you got was understated and elegant, in a modern sense, exciting to drive as nearly any sports car, and yet still comfortable for four.   The elegant little sedan was an instant sensation. In the 1500, BMW not only found the long-term solution to its dire business straits but, more importantly, created an entirely new
    History of the BMW 2002 and the 02 Series

    History of the BMW 2002 and the 02 Series

    In 1966, BMW was practically unknown in the US unless you were a touring motorcycle enthusiast or had seen an Isetta given away on a quiz show.  BMW’s sales in the US that year were just 1253 cars.  Then BMW 1600-2 came to America’s shores, tripling US sales to 4564 the following year, boosted by favorable articles in the Buff Books. Car and Driver called it “the best $2500 sedan anywhere.”  Road & Track’s road test was equally enthusiastic.  Then, BMW took a cue from American manufacturers,
    The BMW 2002 Production Run

    The BMW 2002 Production Run

    BMW 02 series are like the original Volkswagen Beetles in one way (besides both being German classic cars)—throughout their long production, they all essentially look alike—at least to the uninitiated:  small, boxy, rear-wheel drive, two-door sedan.  Aficionados know better.   Not only were there three other body styles—none, unfortunately, exported to the US—but there were some significant visual and mechanical changes over their eleven-year production run.   I’ve extracted t
  • Upcoming Events

  • Supporting Vendors

×
×
  • Create New...