No crank, no start, clicking from front ECU

DAVID W. SCOTT

MEMBER
2003 MITSUBISHI ECLIPSE
3.0L
V6
2WD
MANUAL
130,000 MILES

The car won't start or even spin over. No dash light or headlights but some power (power windows).

There is a constant clicking noise coming from the front ECU. I pulled the ECU cover and tried to determine by touch which relay was clicking but I can't tell. Battery is old but voltage is good.

When it happened before I got lucky, and it started fine but I don't know exactly what corrected it. I suspect it's a sensor somewhere that triggers this, but I've messed with different things whenever it happened. Things like it seems to happen if I turn the headlights off before shutting off. An open door doesn't ding like it should when this happens, it's a steady high-pitched sound. If left alone the clicking will drain the battery.

Disconnecting the battery doesn't clear it out. I thought clearing the codes fixed one time but that apparently was a fluke.

I don't suspect a bad ECU relay because it is working (clicking) but the signal it receives is probably intermittent. Then again, I just thought the relay might not be latching for some reason. I just need to find which one is clicking so I know where else to look.

1 Reply

JACOBANDNICKOLAS

MECHANIC
109,709 POSTS

Hi,

Are the windows the only electrical component working? If so, have you checked the fuses to see if there is power to any of them?

There are what are called fusible links in the engine room relay box. These supply voltage to multiple fuses and could be related to the issue. See pics 1 and 2 below. Make sure they are in good condition, the connections aren't corroded, or anything that is out of the ordinary.

Let me know as much as you can as far as what works and what doesn't.

Take care,

Joe

See pics below.

Images (Click to make bigger)