RE: [DML] RPM Relay/ECM/Pulse generator Diagnostics

["Tom Tait" <TTait@xxxxxxxxxx>]

I'm concerned because my failure coincides with replacing the cap and rotor and I'm afraid I disturbed something at the distributor,  When I last had time to look at the car a few days ago (my wife is sick so the car is on the back burner for a bit)  I was able to determine that the RPM relay was not closing, but was getting a 3 volt DC signal as read by my meter.  I now understand that the signal is a pulse and cannot be read realizably in a DC voltage mode.

I'm happy to replace the relay, and am looking at the upgraded relay from SpecialTauto,  but I'm really more concerned that I screwed something up elsewhere.  My understand was that the signal went from the distributor to the ECM and then to the relay.  I'd love to verify proper operation of each of these components.

What do I really need to do?  Check Ohm reading at the rear firewall connector and verify 600 ohms - right?  At all times or only when cranking?  This tells me the distributor is ok, but maybe not the ECM?  I do suspect that I need to reset the timing at the distributor - when installing the cap I inadvertently knocked the Rotor, although I tried to put it back in its original position I probably screwed that up.  Could the timing being out cause the RPM relay to malfunction?

It just seems like a heck of a coincidence that I would lose an RPM relay while messing with the distributor.

Tom 

-----Original Message-----
From: dmcnews@xxxxxxxxxxxxxxx [mailto:dmcnews@xxxxxxxxxxxxxxx] On Behalf Of doctorDHD@xxxxxxx
Sent: Monday, July 04, 2005 5:36 AM
To: dmcnews@xxxxxxxxxxxxxxx
Subject: [DML] RPM Relay/ECM/Pulse generator Diagnostics

 
 
Tom,
 
What exactly are you trying to accomplish or find out?
 
The "signal" going to the RPM relay is on the WS wire (white with a slate
stripe) and comes from the Ignition ECU to ignition coil  primary connection.  
It is a "tach" signal and thus you should be able  to get a reading with a standard automotive diagnostic tachometer.
 
If this info does not help, please give us more details about what you  need.
 
D² & 6530
Currently undergoing a water pump change.

Message:  6         
Date: Sat, 2 Jul 2005  15:16:59 -0700
From: "Tom Tait"  <TTait@xxxxxxxxxx>
Subject: RPM Relay/ECM/Pulse generator  Diagnostics

Is there a procedure available to test the signal going to  the RMP relay?  Can the relay itself be tested with a 12 VDC power  supply or do I need an alternating/pulsing current?

Tom Tait  #10902



 
Thank  you,

Dave



"Just Say  NO, to the COUCH POTATO!"®


To see how go to _www.tvpedaler.com_ (http://www.tvpedaler.com/)   



[Non-text portions of this message have been removed]





To address comments privately to the moderating team, please address:
moderators@xxxxxxxxxxx

For more info on the list, tech articles, cars for sale see www.dmcnews.com

To search the archives or view files, log in at http://groups.yahoo.com/group/dmcnews
Yahoo! Groups Links



 






To address comments privately to the moderating team, please address:
moderators@xxxxxxxxxxx

For more info on the list, tech articles, cars for sale see www.dmcnews.com

To search the archives or view files, log in at http://groups.yahoo.com/group/dmcnews 
Yahoo! Groups Links

<*> To visit your group on the web, go to:
    http://groups.yahoo.com/group/dmcnews/

<*> To unsubscribe from this group, send an email to:
    dmcnews-unsubscribe@xxxxxxxxxxxxxxx

<*> Your use of Yahoo! Groups is subject to:
    http://docs.yahoo.com/info/terms/