Headlights get brighter when handbrake is applied.

Quote:

---

Originally Posted by Aaron IIA

I took some measurements last night. With the engine running, headlights and cabin fan on high, the body floated up 0.9 volts above battery earth. With the handbrake off, around 12 amps were flowing through the handbrake cable. With the handbrake on, around 15 amps were flowing through the handbrake cable. No current flowed through the handbrake cable when cranking or with lights and fan off. It would appear that the battery to chassis and chassis to block earth cables are functioning, but the connection at the body is not.

Aaron.

---

It takes around 15 minutes to trace your finger down the main battery earth cable, find the body earth lug, dismantle, clean and re-tighten it. The battery may have to come out to access the lug.

It's using the hand brake as an earth, as said earlier the cable might melt when cranking.
I had it happen on a D2, it caused a small fire in the centre console and fried my ECU, so get you earths checked asap.

Quote:

---

Originally Posted by JDNSW

Yes, that's exactly what I expected.

If the battery earth had gone to the body or chassis rather than the block, it is likely that you would be having starting problems as well as lighting problems.

---

On my series 1 (1950) I unbolted the handbrake and the lights would not work at all. When I bolted
it back up everything was fine. [thumbsupbig]

After fitting some new spotlights and re-wiring the aircompressor last weekend, I chased the bad earth. The battery to body and chassis earth cable was loose at the body mounting bolt. It was also tarnished, but not corroded. After cleaning and tightening, the body came back to the same potential as the battery.

Aaron.