Jump to content


Rescuing the Ignition Relay


Recommended Posts

I'm reinstalling the dash, and checking wiring, connections, etc. I was not getting power to the ACC or IG busses in the fuse panel. I could hear the ignition relay 'click' with the key in the Acc or ON positions, and I could see power from the fusible link getting to the white-red wire at the bottom of the C6 connector. I pulled the dash back enough to back-probe the ignition relay connector, and confirmed that voltage was getting to the ACC and IGN contacts, but was not passing through when the relays were energized.

I removed the ignition relay, and further confirmed by testing that both relays would click, but would not pass power through their contacts.

This forum says the relay is not easily replaced, so I thought I would dig deeper.

Start by bending back the cover tabs (circled), but try to be careful of the ground tab (arrow):


 Open the relay while trying the use the ground tab as a 'hinge':


Admittedly, these relays appear to be in sad shape. But further examination showed that the contacts (circled) were actually in excellent condition, but there was a buildup of rust and crud between the coils and armatures (arrow):


Note that by this time, I had broken the ground tab (square), which appears to have been spot-welded to the relay case.

Clean up the crud with a folded over piece of 1000-grit:


Retest both relays to make certain they are really snapping closed and making good contact.

Put the relays back into the cover, and re-crimp the tabs to hold it together.

If you broke the ground tab, solder a pigtail to the tab.


Note that I tried, but could not reliably solder the tab back to the cover where it had originally been welded.

When reinstalling the relay, be sure to put the existing ground wire under the relay mounting tab, and then you can put your pigtail ground under the same mounting bolt on top of the relay mounting tab.

If the contacts had not been in good condition, I would not have done this, but would have instead resorted to wiring in new relays,



Edited by Roberts280Z
remove extra pic
  • Like 2
Link to comment
Share on other sites

2 hours ago, Roberts280Z said:

If the contacts had not been in good condition, I would not have done this, but would have instead resorted to wiring in new relays,

Not me... I would have wired in new relays. I've been beat down working on the electrical of these old Datsuns and now I replace rather than mess with the 40+ year old electrical stuff for the most part.

Link to comment
Share on other sites

ETI4K - the cover didn't look like it had been tinned. I just tried plain old soldering, but even when it looked like I had a join to the cover, it popped off easily.

cgsheen1 - I'm getting to that beat-down state, can't get the turn or hazard signals working now, I'm working through it one circuit at a time.

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
  • Create New...

Important Information

By using this site, you agree to our Privacy Policy and Guidelines. We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.