1088a1 chasing electrical gremlins

[Benlin]

If this has already been asked then lead me to the post, and thanks.
I have a 1088a1 2004 with Cat 3126, that keeps shutting down from low power to ECM, the alternator is putting out stable power up in the correct range on both 12 and 24. The panel has 28v?? on the pre ignition side and 22v or less on the ignition side, (I have a huge drain on the 24V side in the ignition). I have isolated every single thing I could find, plugging and unplugging every fuse/breaker/relay etc. I could find and the gauge never raises, (has come up into normal operating range a few times but quickly drops again) so something is shutting down the draw and then drawing again. I have found the R15 diode that is right below AUX COOLER K15 is getting very hot. Any thoughts or history with such a demon, would be of great help.

 

[Suprman]

Could it be the circuit board itself they do go bad

 

[Benlin]

Looks like I got it, a loose cable was found on the hi amp solenoid, on the 24v side. Between the constant 24v and the ignition 24v side. Thank you for your response.

 

[Ronmar]

I was going to ask how you determined it was a high load. A bad connection will do the same thing with normal loads…

R-15 is a resistor. On the A1 they did away with the need for 12V and 24v relays, and they used only 12v relays(4 and 5 pin). On the relay circuits that use a 24v source for the coil, they installed resistors to dissipate the excess current. The aux fan relay is always energized like the fan solenoid, unless the fans are engaged, so that resistor will probably get warm…