MK2 98>00 Headlight Earthing Block Re-location

One common problem with the MK2 MX5 is caused by the headlight earthing blocks. They corrode causing a bad earth which will make your headlights dim and often can cause the bulb connectors to overheat and melt.

The solution is to keep the earth blocks in good condition and the connections clean, but the location is less than ideal for easy access and preventative maintenance as they are hidden underneath the headlights and require the lights to be removed for access to the earths.

We recommend that the first time you do this maintenance you move the earth blocks from their original location to an area more accessible...

and here is how:

Required parts:

1 x Bolt (m5 or m6)
1 x Nut (to fit bolt)
1x Drill sized for clearance of selected bolt (5.5mm or 6.5mm)

Remove your headlights buy undoing the 4 10mm headed bolts holding the air guide/slam panel and then the 2 bolts on each headlight also with 10mm heads. The headlights can then be wiggled out, be careful not to break them, but with enough pushing, pulling and wiggling, they will come out.

Passenger side

  1. The passenger side is very easy to relocate.
  2. Locate the earth block under the headlight.
  3. Bolt the 10mm headed m6 bolt that holds it down.
  4. Bolt it back in place at the already provided hole as shown arrowed in the pictures below. You do not need to extend the wires, they will reach easily. Be sure to clean the tab of the earth block well before bolting in place and apply a good coating of copper grease to the tab, mounting area and bolt.


Drivers side

    1. Drivers side is a little more complicated, but still within the grasp of an amateur.
    2. Take your drill and drill a hole in the area located by the arrow in the pictures below. The picture shows where I have drilled.


  1. Now it is a good idea to unbolt the earth block, clean the tab well. Also take time to clean up the new mounting area you have just drilled. You want to see bare metal under the area the tab sits.
  2. Hoover up or blow out any left over swarf from the drilling and cleaning of the hole.
  3. Now apply a good coating of copper grease to the bare metal areas, around the new hole, and all over the tab of the new mounting area. Also grease your new nut and bolt and use these to bolt the earth block through your newly drilled hole.
  4. Refit your headlights fitting the 2 bolts each side, followed by the 4 slam panel bolts.

 You now have relocated your earth blocks and they will be a lot easier to access and maintain in the future.