One channel dead, 12 A fuse blown, R17 Open, Outputs Shorted, and crack in PCB.

bogus post, fuse told ,is not correct name and now told not it is not blowing,(ouch)
5.3L V8 , now told, ( this fact puts you into the right chapter of the service manual for sure electrics..)
bogus post#2, fuse PCM-B are not blowing but why are you talking about it at all.?? sure other posts else where? guessing?

stop listening to other guessing what is wrong,
all we know is 12vdc power surge, of some kind,
if you looked at the drawings the things that can fail here are huge(vast). I invite you to read the service manual.
yes fuel pumps do short, want to see a pro Duane on youtube , and his scope showing bad commutator segments of a fuel pump?
huge current spikes, sure but that is a guess. (the video is how to find things going bad before they hard fail dead)

so not told , is engine still dead, ? cranks but does not start, , and did you know dead is the most easy failure of all
to find, safe and sound, not moving and dead is easy to test. (like no spark or fuel pressure dead,etc)
hard jobs are failing moving
or is intermittent.
or only in 3 gear
or only up hill.
or only in left turns. (add endless list here) but the point is made.

dead is bliss in my book , and simple tests find out why.
no voltmeter
no scan tool?(real)
no tools at all?
redux #1 (new truths)

here is the manual, I am looking for a more detailed version

DODGE RAM. (per OBD2 is OBD1 dodge unique) USA LAWS.
all plugs dead, we check them all. not just one.
USA spec car? v10.
learn that all ECU/PCM cuts fuel if the ECU detects lost spark
it cuts fuel so spark is first, on all spark plugs
are the plugs over 100k miles old?
ASD WORKS LIKE THIS IF ECU SEES SPARK DEAD ECU DISABLES THE ASD, THIS PREVENTS CRASH AND BURN AS SEEN ON TV.
ALL FUSES GOOD RIGHT> WE TEST THEM.

KEY ON CEL MUST GLOW, THIS KEY ON EVENT IS THE LAMP TEST. IT MUST GLOW ONCE AND CAN GO OUT. AFTER.
IF NOT THE PCM LOST POWER, CALLED BLOWN FUSE.

THE CURE IS BASED Purely off ASD dead.
on all cars Chrysler. even jeeps,
The PCM seens any thing dangerous ASD drops
or even fails top close;. once

my guess is you do not know how to test fuses?????
there are 3 tests, in increased value.
1; gander at it ,looks blown it is. but looking good can be bad.
2: Ohms test can lie if hair line cracks here. but is great test.
3:live test, 12vdc, key on , both sides of fuse 12vdc is good
12 vdc in, and 0v out is a bad fuse (or bad fuse and shorted load)
nothing on earth bets a live test, pass /fail .

learn now the CEL lamp works key on (self test)
learn too how to do THE SM book ODB1 CEL code flash test.'called then Diagnostic jumper.
https://eautorepair.net/Marketing/Default.asp

in 1995 USA this ECU has DLC connector, that has jumper pair of pins called Diagnostic, test.

quote

When the CHECK ENGINE light comes on and stays on (after start-up), this indicates that a code (or codes) has been stored in memory. To retrieve this information for purposes of troubleshooting, cycle the ignition switch ON- OFF- ON- OFF- ON within five seconds. The check engine lamp will then flash the DTC(s). Each code, if there is more than one, will be preceded by a four second pause, to distinguish it from the previous code. An example of a DTC would be as follows:

• Lamp on for two seconds, then turns off.
• Lamp flashes four times, then pauses, then flashes one time.
• Lamp pauses four seconds, then flashes four times
• Lamp flashes seven times.
• code 47, per SM.

codes 43 is ASD relay is dead. bad
code 43 is any bad spark coil , kills ASD dead.
53 dead ECU
54 cam sensor dead., code 11 is crank sensor dead.
63 dead ECU
55 = end of report

Jeep WJ !
you only have 2 choices
buy the fsm, or find it here. below or use alldata.com , it's all there.
or check all fuses.

each fuse has many loads. so test them all or read the FSM..
all cars. made.
http://www.jeep4x4center.com/knowledge-base/index.htm?utm_source=cj#service

lets see what is there. fuse 23 blown kills cruise. and brake lamps dead. or PCM in limphome and that can kill cruise,
is CEL out running? if not , CRUISE can be suspended for GOOD reasons, (safety) and more on newer cars...
-----------------------------------------------------------------------
now seats. not the power seat motors. but heaters.
both sides, dead, bottom and back side?
both sides, have a switch, that the BCM watches.
the BCM controls the seat heat.
above 105F ambient this system shuts down.
in the jeep dealer he connects the DRB and sees whats wrong fast.
if the switch LED are dead key on, the fuse is blown.
are yours? dead? (page 8g-5 , fsm)"heated systems"
if the fuses are good, and the lamp glows, at seat it will take
a dealer DRB tool to find true cause or all day with an ohm meter
per above heated systems pages.

here is how seat heat works, it not like a 1995 car.
the BCM watches that seat switch
it sees (monitors) what you do , then sends (by digital COMMAND via PCI bus to) SM.
power (12vdc) to the heater with the "SEAT MODULE"doing the heavy lifting (drivers)
THE SM drives the seat.
black org. wire to diver back heater. and white to bottom heater
so ill assume the SM lost power, (wild guess)
i can not find the fuse that runs SM module.
but if the LED is out, then the fuse is blown and gee, that is easy to find, just looking.
i dont have a searchable FSM, to scan for SM fuse.

Probably took out the output transistors for that channel. Is the unit dead now? Usually in these models, if the outputs go, it takes out the main power fuse.

I would also replace 2sa992 (2pcs) and 2sc1845 on preamp board- sometimes they look ok when you test them by regular meter. Check 1.2 kOm and 4.7ohm resistors at preamp pcb. Check diodes on output pcb (could be smd type, connected from base of output transistors to emitter i think)

If you can watch the fuse kind of twitch. Most likely you have somthing shorted in your output amps. ( the ones on the heatsink underneath PCB) you'll probolly need a tech for this one to change out the transistors. Still under warranty?

Your audio output transistors are shorted and your unit is staying in "protect " mode to protect your speakers from 40 to 60 volts that is being sent at them from the shorted outputs. If you can use a meter you won't need the schematic MOST likely because the outputs are USUALLY the only parts that short out. The output transistors( or chip ) are mounted to the large, finned heatsink. The #'s on the transistors start with "2SA-" and "2SC-" followed by numbers. There are two output transistors per channel. If your unit uses an IC for audio output then the # on the IC will be "STK-" followed by numbers. These parts are available from tritronicsinc.com. Good Luck!

barneyluc

The problem is not the transformer. You now have shorted output transistors at the very least. By corssing the wires you presented a zero(0) ohm impedence load to the output section. It quickly went into overload. Before the fuses had a chance to open up, the outputs fried. This unit will require new output transistors and perhaps the previous driver circuit will require parts as well. Figure on $20-$50 in parts plus hte local labor rate for the repair.

Dan

Hi Ho There,

The speakers can be driven to make sound by several different power devices, These devices can be FET's or Transistors, or a output Integrated circuit.

All of these devices can be damaged by shorting the speaker wires I suspect thats what has happened in your case...

The manufacturers provide internal p[rotection and this can be in the form of a fuse which will beaccessible from the ouitside of the case.

Have a good look to see if there are any fuses there that are blown that you can replace yourself...Please replace with the same value type as fitted already...

If you cant locate any blown fuses then it will need to be taken to a service person to strip the cover off to see if there are any fuses that can be replaced inside....otherwise it will need to be repaired especially if the output device is damaged in any way..

If you are lucky it should be just a fuse as the "wifey staple" would most likely have shorted out omly the one channel, and as you say both channels dead then its more likely to be a fuse that supplies all the output stage devices that has disrupted..

Good huntind

YUBEUT.