Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

Or, hide this message: temporarily or permanently

ECM Ground Circuit Check

- First check the ECU ground circuit.
- If it is faulty, repair it.
- If it is normal, the ECU could be faulty, so replace the ECU with a known good one and check if the symptoms appear.

- Measure the resistance between the ECU ground terminal and the body ground.

Resistance: 1 Ohm or less

- Disconnect the ECU connector, check the ground terminals on the ECU side and the wire harness side for bend and check the contact pressure.