My 620 build thread.

[J's 620]

Yes I hear it, and feel the click when I hold the relay. 

[datzenmike]

What I'm trying to determine is, is the relay sometimes not clicking the times he lights don't switch to high beams. If it clicks every time the switch is activated, then the relay is at fault. I'm guessing that the relay can be removed and very carefully pried apart. The contacts inside are likely corroded. Fold a fine piece of emery paper and draw it through the closed contacts to polish them.  

[J's 620]

On 7/25/2021 at 9:55 PM, datzenmike said:

What I'm trying to determine is, is the relay sometimes not clicking the times he lights don't switch to high beams. If it clicks every time the switch is activated, then the relay is at fault. I'm guessing that the relay can be removed and very carefully pried apart. The contacts inside are likely corroded. Fold a fine piece of emery paper and draw it through the closed contacts to polish them.  

It seems like the relay does click every time the switch is activated. Yesterday I tried getting under the hood of the 78 to grab it’s relay to see if that would fix the issue and was ran off by some wasps. I took care of that nest this morning so I’ll try again when I get home. 
 

well that extra relay was a dud..... it causes the hi beams to come on instantly and stay on regardless of hi beam switch position. 

Edited July 28, 2021 by J's 620

[J's 620]

On 7/25/2021 at 9:55 PM, datzenmike said:

What I'm trying to determine is, is the relay sometimes not clicking the times he lights don't switch to high beams. If it clicks every time the switch is activated, then the relay is at fault. I'm guessing that the relay can be removed and very carefully pried apart. The contacts inside are likely corroded. Fold a fine piece of emery paper and draw it through the closed contacts to polish them.  

 This is a hard relay to remove from under the dash, I need a short screwdriver or a Phillips/JST tip in a small ratchet type tool ( I have one) I just don’t see how I’m going to get the screws back in the holes. 
 Anyway there is a screw on the face of it, where the plug connects to the spade terminals... mike are you saying take this thing apart carefully and try to sand up the contacts INSIDE?? 
 The 78 does not have the same relay, they are different part numbers, and the wiring was a different color. 
 Mike can you post a picture of the diagram you have?

 Ah I found one. 

Edited August 4, 2021 by J's 620

[J's 620]

I devoted some time last night to opening this relay up, and yeah it’s not functioning like it should. Seems like it’s lost the ability to pull the contractor to the low beam side. In a neutral position it favors the high beam side. It has a little spring that didn’t make a difference wether it was in or out. 
 Anyway I used electrical tape to keep the contact closed in the low beam position. I don’t have any other relays quite like this one. Is there a typical 4pin relay I can substitute this one with??

[datzenmike]

 

There are lots of relays on the 720. This one has two connections for the energizing coil at the bottom. Above is a common and a NO (normally open) and a NC (normally closed) NC is it's off position. When the coil is powered it connects the common to the NO

 

You can buy similar ones by Bosch at NAPA