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Problems with wires: B+, M-Relay and EFI+ wires from ECU

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9K views 4 replies 3 participants last post by  twinturbosupra94  
T
#1 ·
Well after tracing the wires, making sure that the fuses are all good, checking all the relays, I have come down to the wires being bad.

For everyone that has no-idea what I am talking about, I am referring to the 12V B+ wire that feeds to the ECU, which in turns sends out a 12V signal to the relay via a M-Relay wire, which flips the relay and allows the EFI wires to supply 12V back to the ecu.

Here is a diagram (focus only on the Black/Yellow, Gray and Red/Black wire.

Image


Image


Looking at both diagrams, the wires are independent and are very much straight wires from the fuse box to those two connectors that are under the fuse box straight to the ECU. They are practically direct connections

After checking one of the wires (Black/Red wire) I got a reading of 5.6M Ohms using my fluke digital voltmeter. Does that mean the wire is fried or something? I check other wires and they ring up direct connections, no resistance, but for some reason, this does get resistance. As for the B/Y wire, I didn't get any connection. I didn't test the gray yet but will tomorrow.

So my question is what do you guys think regarding the 5M ohms? Is it that easy for a wire to fry?

Any input will be appreciated.


P.S. The fuel pump works....checked using a bucket and disconnecting a fuel line.
 
#4 ·
Not Understanding the question

Don't really understand the problem.

But it seems you are saying that you are not getting powered up when you turn the ignition on.

Start like this:
Open the hood.
Remove the cover on J/B2 (the big fuse box by the battery)
Remove the EFI1 fuse (30amp)
Connect your Digital Voltmeter to the battery ground.
Check for voltage at the EFI1 fuse position (check both sides, only one should have voltage)
Put the EFI1 fuse back in.
Check for voltage at the access point on the fuse (you should have voltage on both sides)

If ok, then

Next:
Do the same for the AM2 Fuse

If ok, then

Next:
Go inside the car to J/B1 (fuse box in the kick panel)
Check for Voltage at the 7.5a IGN fuse with the key ignition switch ON.

If ok, then

Next:
Access the Engine Control Module.
Check for positive voltage at Connector E10 (the smaller connector) pin1 which is a Black with orange stripe wire.
Make sure the Key is in the ON position when you check for voltage.

If ok, then

Next:
at the same connector E10 Check that there is positive voltage at pin 24 (Gray wire).
This should be checked from the back of the connector (with connector plugged in) and the key in the ON position.

If ok, then

Next:
Go back to J/B2
Remove the EFI main Relay
Check for voltage at Pin 1 of the relay connector (closest to firewall)
Again, Key should be ON.

If ok, then

Next:
Check For Voltage at pin 3 of the relay connetor (closest to the fender)


If ok, then

Next:
Check for Continuity to ground from Pin 2 (closest to front of car) of the EFI main Relay connector to ground.

If ok, then

Next:
Plug the EFI main relay back in.
Turn the key on
At DLC1 (Data link connector under hood) check for Voltage at B+

If all that comes up Ok, then you have a problem elsewhere or EFI main relay is bad.

Ishii
 
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