ECM 1 fuse blowing 1987 chevy

[Yellowcat]

I touched the probes on all different pins of the ESC  just to see if anything would happen...... it every time it just stays on the letters OL. I done all these three separate tests with the ignition key switch off

[Yellowcat]

Also as I have stated before the wires going to the fuel relay do not have power when turning the ignition key on the only wire that has constant power when the key is off is the orange wire

[bd]

Don't be alarmed by the 'OL' measurement on your meter.  OL means overload, indicating the circuit is effectively open from the perspective of the ohmmeter.  The ESC module, unlike the EGR solenoid and EAC valve solenoid, contains an integrated circuit with very high internal impedance that conducts microamps of current.  The EGR and EAC solenoids are electromagnets with moderately low impedance flowing approximately 1 amp each.  That's 6 orders of magnitude difference.  The primary concern was to discover whether the ESC module is shorted.  It is not. 

Simply for the sake of interest, recheck the ESC pins reversing the probe polarities to see if there is any difference and let us know. 

Regarding the fuel pump, will the engine start and run?

[bd]

You didn't say if the EGR and EAC solenoids measured greater than 10 ohms...?

[bd]

What does the meter indicate if you touch the two ohmmeter probes together?

[Yellowcat]

The multimeter buzzes and goes to 0 when the probes are touched.. the EGR and EAC tested both at 37ohms. The truck will not start and run because I can't get power to fuel relay like it's suppose to have or power to the pump when I tried to  jump it from the pigtail on the fuel relay. Why is there no power to the green and white wire on e fuel pump relay when you turn ignition on??

[bd]

See below.

[Yellowcat]

The truck cranks today and runs after cranking for 10 seconds or more. Still the fuel pump relay us nit getting all the signals. I post a link to videos to watch it. Still the pump is not priming like it did for 2 seconds

[Yellowcat]

https://youtube.com/shorts/3pHSupQrGhI?si=GTz1wP2Y-YJmjgrm

[Yellowcat]

https://youtube.com/shorts/3pHSupQrGhI?si=zqMyS2clF9DZK1x-

[Yellowcat]

The green and white wire going to the fuel pump relay is coming only from the ECM? If it is and the ECM is faulty?

[bd]

With the fuel pump relay connected to its wiring harness, will the fuel pump run as long as you feed B+ to the RED/WHT pigtail?  Using an incandescent test light clipped to a good, clean ground (not your voltmeter), probe the DK GRN/WHT wire connected to the relay and start the engine.  While the engine is cranking and running, does the DK GRN/WHT wire illuminate the test light?

[Yellowcat]

The fuel pump will not run when I put B+ to the pigtail when engine is not running. When I grind the engine10 to 15 seconds to finally get it running I probe the red and white striped pigtail wire it is hot. I posted a video of this. I probed the green/white when engine us running and it does not illuminate the test light.   https://youtube.com/shorts/v3nxZngrtwk?si=O65XhmUublzyfdTf

[bd]

Reference and familiarize yourself with the diagnostic charts that I previously posted.  Verify perfect power and ground continuity to the ECM.  Check continuity of the DK GRN/WHT wire between the ECM and fuel pump relay.  Clean the harness connections to the ECM using some DeoxIT D5 or CRC QD Electronic Cleaner, etc.  You may need to very carefully re-tension the terminal connections to the ECM and verify that none of the terminals are distorted, broken, or heavily corroded.