1994.5 - 1997 7.3L Power Stroke Diesel  

truck quit on me... need help plz

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  #46  
Old 02-05-2013, 07:07 PM
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Here is fords procedure for the test .
Your truck may have run with a bad alternator but it was the battery's that kept it going ( good battery's)
Hope this helps




G1 CLEAR AND ATTEMPT TO REGENERATE DTC 0344, 0341 OR 0340
Plug in NGS Tester.
Clear continuous DTCs with NGS Tester.
Crank engine while monitoring rpm PID.
Does PID indicate crank rpm?

Yes: GO to «G2».
No: GO to «G3».

G2 RERUN CONTINUOUS FOR DTC 0344 OR 0341
Warm up engine to normal operating temperature.
Increase rpm to 3300 rpm for 2 minutes.
Key off.
Rerun continuous codes.
Are DTC 0344 or 0341 present?

Yes: GO to «G3».
No: Fault is intermittent. GO to «G12».

G3 CHECK CMP SIGNAL RETURN CIRCUIT 796 (LB)
Unplug CMP sensor.
Key off.
Check resistance between Pin A on the CMP connector and chassis ground.
Is resistance less than 5 ohms?

Yes: Ground is OK. GO to «G4».
No: GO to «G9».

G4 CHECK CMP CIRCUIT 351 (BR/W) FOR VREF
(CMP sensor unplugged)
Key on.
Check voltage between harness connector Pin B and chassis ground.
Is 5 volts ± .5 volts present?

Yes: Circuit 351 (BR/W) is OK. GO to «G5».
No: SERVICE VREF circuitry. GO to «B1».

G5 CHECK CMP CIRCUIT 795 (DG) FOR B+
(CMP sensor unplugged)
Key on.
Check voltage between harness connector Pin C and chassis ground.
Is B+ present?

Yes: GO to «G6».
No: Circuit 795 (DG) is shorted or open. GO to «G7».

G6 CHECK CMP CIRCUIT 795 (DG) FOR SHORT TO B+
(CMP sensor unplugged)
Key off.
Unplug PCM.
Inspect 104 pin connector and repair if required.
Key on.
Check voltage between harness connector Pin C and chassis ground.
Is B+ present?

Yes: SERVICE short to B+ in Circuit 795 (DG). REASSEMBLE system. CONFIRM fix with NGS Tester PID "RPM" and by repeating«G1» and «G2».
No: Circuit 795 (DG) is OK. REPLACE CMP sensor.

G7 CHECK CIRCUIT 795 (DG) FOR SHORT TO GROUND
(CMP sensor unplugged)
Key off.
Unplug PCM.
Inspect 104 pin connector and repair if required.
Key on.
Check resistance between connector point C and chassis ground.
Is resistance less than 5 ohms?

Yes: SERVICE short to ground in Circuit 795 (DG). REASSEMBLE system. CONFIRM fix with NGS Tester PID "RPM" and by repeating «G1» and «G2».
No: GO to «G8».

G8 CHECK CIRCUIT 795 (DG) FOR OPEN
(CMP sensor unplugged)
(PCM unplugged)
Key off.
Attach 104 pin breakout box.
Leave PCM disconnected.
Key on.
Check resistance between harness connector Pin C and breakout box Pin 49.
Is resistance less than 5 ohms?

Yes: Open is at PCM Pin 49. INSPECT PCM connector and PCM pins. SERVICE as necessary. REASSEMBLE system. GO to «G11».
No: REPAIR open in Circuit 795 (DG). REASSEMBLE system. CONFIRM fix with NGS Tester PID "RPM" and by repeating «G1» and «G2».

G9 CHECK FOR OPEN IN CMP GROUND CIRCUIT 796 (LB)
(CMP sensor unplugged)
Key off.
Unplug PCM.
Inspect 104 pin connector and PCM pins and repair as required.
Install breakout box.
Leave PCM disconnected.
Measure resistance from PCM Test Pin 65 to harness connector Pin A.
Is resistance less than 5 ohms?

Yes: Circuit 796 (LB) is OK. GO to «G10».
No: SERVICE open in Circuit 796 (LB). REASSEMBLE system. CONFIRM fix with NGS Tester PID "RPM" and by repeating «G1» and «G2».

G10 CHECK FOR CMP GROUND THROUGH PCM
(CMP unplugged)
(Breakout box attached)
Key off.
Attach PCM to breakout box.
Measure resistance from PCM Test Pins 25, 51, 76, 77 and 103 to ground.
Is resistance less than 5 ohms?

Yes: PCM internal ground not supplied to Pin 65. REASSEMBLE system. GO to «G11».
No: REPAIR open in Circuit 570 (BK/W) and Circuit 57 (BK) as required. REASSEMBLE system. CONFIRM fix with NGS Tester PID "RPM" and by repeating «G1» and «G2».

G11 CONFIRM PCM FAULT
Rerun «G1» and «G2».
Are faults still present?

Yes: REPLACE PCM and RERUN.
No: System is OK.

G12 FIND INTERMITTENT
Key off.
Unplug PCM.
Inspect 104 pin connector and PCM pins and repair as required.
Install breakout box.
Attach PCM to breakout box.
Unplug the IDM relay in the engine compartment power distribution box to prevent engine from starting.
Run voltmeter test leads between breakout box Test Pins 49 and 65.
Rotate engine by hand until voltage toggles from B+ to between 0.3 and 2.7 volts.
Did lower voltage toggle fall between 0.3 and 2.8 volts?

Yes: GO to «G13».
No: GO to «G3».

G13 CHECK HARNESSES FOR INTERMITTENT
(Breakout box installed)
(PCM attached to breakout box)
(IDM relay unplugged)
(Voltmeter test leads between breakout box Test Pins 49 and 65)
Rotate engine by hand until voltage stays at lower toggle of between 0.3 and 2.7 volts.
Wiggle harnesses and watch for voltage jump to B+ or 0.0 volts.
Did voltage jump to B+ or 0.0 volts?

Yes: DETERMINE source of intermittent and REPAIR. CONFIRM fix with NGS PID "RPM" and by rerunning «G1» and «G2».
No: Intermittent not found. REASSEMBLE system using dielectric grease. CHECK with NGS Tester PID "RPM" and by rerunning «G1» and «G2».

B1 CHECK VEHICLE BATTERY POWER CIRCUIT
Key off.
Disconnect PCM. Inspect for damaged or pushed-out pins, corrosion, loose wires, etc. Service as necessary.
Install breakout box and connect PCM to breakout box.
Key on, engine off.
Measure voltage between Test Pins 55, 71 and 97 to Test Pins 25, 51, 76, 77 and 103 at the breakout box. Note voltage.
Measure voltage across battery terminals. Note voltage.
Are both voltages greater than 10.5 volts, and are both voltages within 1.0 volt of each other?

Yes: GO to «B2».
No: Key off, RECONNECT sensor (if applicable). GO to «A1».

B2 CHECK VREF VOLTAGE
Key on, engine off.
Breakout box installed, PCM connected.
Measure voltage between Test Pin 90 and Test Pin 91 at the breakout box.
Is voltage between 4 volts and 6 volts?

Yes: GO to «B3».
No: Less than 4 volts, GO to «B5». Greater than 6 volts, GO to «B4».

B3 CHECK VREF AND SIG RTN CIRCUITS FOR CONTINUITY
Key off.
Sensor that sent you here disconnected.
Breakout box installed.
Disconnect PCM.
Measure resistance between Test Pin 90 at breakout box and VREF circuit at vehicle harness connector of the sensor that sent you here.
Measure resistance between Test Pin 91 at breakout box and SIG RTN circuit at vehicle harness connector of the sensor that sent you here.
Is each resistance less than 5.0 ohms?

Yes: Reference voltage OK. REMOVE breakout box. RECONNECT all components. RERUN Scan Tool Diagnostic Test.
No: SERVICE open in VREF or SIG RTN circuits. REMOVE breakout box. RECONNECT all components. RERUN Scan Tool Diagnostic Test.

B4 CHECK FOR EXCESS VOLTAGE ON VREF CIRCUIT
Key off.
Breakout box installed.
Disconnect PCM.
Disconnect NGS Tester.
Key on, engine off.
Measure voltage between Test Pin 90 at the breakout box and battery ground.
Is voltage less than 0.5 volts?

Yes: REPLACE PCM. REMOVE breakout box. RECONNECT all components. RERUN Scan Tool Diagnostic Test.
No: SERVICE short to power in vehicle harness. REMOVE breakout box. RECONNECT PCM and sensor. RERUN Scan Tool Diagnostic Test.

B5 SIG RTN CIRCUIT CHECK
Key off.
Breakout box installed.
PCM connected.
Measure resistance between Test Pin 91 and Test Pins 25, 51, 76, 77 and 103 at the breakout box.
Is each resistance less than 5 ohms?

Yes: GO to «B6».
No: REPLACE PCM.

B6 CHECK FOR SHORTED ACCELERATOR PEDAL (AP) SENSOR
Key off.
Breakout box installed, PCM connected.
Disconnect AP sensor from vehicle harness.
Inspect for damaged or pushed-out pins.
Key on, engine off.
Measure voltage between Test Pin 90 and Test Pin 91 at the breakout box.
Is voltage less than 4.0 volts?

Yes: Leave AP sensor disconnected. GO to «B7».
No: REPLACE AP sensor. REMOVE breakout box. RECONNECT all components. RERUN Scan Tool Diagnostic Test.

B7 CHECK FOR SHORTED CAMSHAFT POSITION (CMP) SENSOR
Key off.
Breakout box installed, PCM connected.
Disconnect CMP sensor.
Inspect for damaged or pushed-out pins.
Key on, engine off.
Measure voltage between Test Pin 90 and Test Pin 91 at the breakout box.
Is voltage less than 4.0 volts?

Yes: Leave CMP sensor disconnected. GO to «B8».
No: REPLACE CMP sensor. REMOVE breakout box. RECONNECT PCM and sensors. RERUN Scan Tool Diagnostic Test.

B8 CHECK FOR SHORTED INJECTION CONTROL PRESSURE (ICP) SENSOR
Key off.
Breakout box installed, PCM connected.
Disconnect ICP sensor.
Inspect for damaged or pushed-out pins.
Key on, engine off.
Measure voltage between Test Pin 90 and Test Pin 91 at the breakout box.
Is voltage less than 4.0 volts?

Yes: Leave ICP sensor disconnected. GO to «B9».
No: REPLACE ICP sensor. REMOVE breakout box. RECONNECT PCM and sensor(s). RERUN Scan Tool Diagnostic Test.

B9 CHECK FOR SHORTED EXHAUST BACK PRESSURE (EBP) SENSOR
Key off.
Breakout box installed, PCM connected.
Disconnect EBP sensor.
Inspect for damaged or pushed-out pins.
Key on, engine off.
Measure voltage between Test Pin 90 and Test Pin 91 at the breakout box.
Is voltage less than 4.0 volts?

Yes: Leave EBP sensor disconnected. GO to «B10».
No: REPLACE EBP sensor. REMOVE breakout box. RECONNECT PCM and sensor(s). RERUN Scan Tool Diagnostic Test.

B10 CHECK FOR SHORTED MANIFOLD ABSOLUTE PRESSURE MAP SENSOR
Key off.
Breakout box installed, PCM connected.
Disconnect MAP sensor.
Inspect for damaged or pushed-out pins.
Key on, engine off.
Measure voltage between Test Pin 90 and Test Pin 91 at the breakout box.
Is voltage less than 4.0 volts?

Yes: Leave MAP sensor disconnected. GO to «B11».
No: REPLACE MAP sensor. REMOVE breakout box. RECONNECT PCM and sensor(s). RERUN Scan Tool Diagnostic Test.

B11 CHECK FOR SHORTED BAROMETRIC PRESSURE (BARO) SENSOR
Key off.
Breakout box installed, PCM connected.
Disconnect BARO sensor.
Inspect for damaged or pushed-out pins.
Key on, engine off.
Measure voltage between Test Pin 90 and Test Pin 91 at the breakout box.
Is voltage less than 4.0 volts?

Yes: Leave BARO sensor disconnected. GO to «B12».
No: REPLACE BARO sensor. REMOVE breakout box. RECONNECT PCM and sensor(s). RERUN Scan Tool Diagnostic Test.

B12 CHECK VREF CIRCUIT FOR SHORT TO GROUND
Key off.
Breakout box installed.
Disconnect PCM.
With all six of the three-wire sensors (AP, CMP, ICP, EBP, MAP and BARO) disconnected, measure resistance between Test Pin 90 and Test Pins 25, 51, 76, 77, 91 and 103 at the breakout box.
Are all resistances greater than 10,000 ohms?

Yes: REPLACE PCM. REMOVE breakout box. RECONNECT all components. RERUN Scan Tool Diagnostic Test.
No: SERVICE short to ground. REMOVE breakout box. RECONNECT all components. RERUN Scan Tool Diagnostic Test.

A1 DIAGNOSTIC TROUBLE CODES (DTCs) 0563/0562/0560: CHECK BATTERY VOLTAGE
Key on, engine off.
Measure voltage across battery terminals.
Is voltage greater than 9.5 volts?
NOTE: DTC 0563 may be a temporary condition with a 24 volt jump start. DTC 0562 may be a temporary condition at crank only.
0563 -- System voltage high
0562 -- System voltage low
0560 -- System voltage malfunction

Yes: F-Series, GO to «A2». Econoline, GO to «A12».
No: SERVICE discharged battery. REFER to Section 14-00 in Body, Chassis Service Manual.

A2 CHECK VOLTAGE AT MAXI FUSE 9
Measure voltage between maxi fuse 9 at power distribution box to battery negative post.
Is battery voltage present?

Yes: GO to «A3».
No: REPAIR open in Circuit 37 (Y) between the power distribution box and the starter relay.

A3 CHECK MAXI FUSE 9
Check maxi fuse 9 power distribution box.
Is fuse blown?

Yes: REPAIR short to ground and REPLACE maxi fuse 9.
No: GO to «A4».

A4 CHECK CIRCUIT 37 (Y) TO RELAY
Key off.
Remove PCM relay.
Remove maxi fuse 9.
Measure resistance between the nonpower side of the maxi fuse 9 to Circuit 37 (Y) of the PCM relay connector.
Is resistance less than 5 ohms?

Yes: GO to «A5».
No: REPAIR open in Circuit 37 (Y) between fuse and relay connector.

A5 CHECK IGNITION FEED TO DIODE
Remove diode from power distribution box.
Key on.
Measure voltage from battery ground to ignition feed side of diode connector.
Is battery voltage present?

Yes: GO to «A6».
No: REPAIR open in ignition feed Circuit 16 (R/LG) or ignition switch.

A6 CHECK DIODE
Key off.
Disconnect diode.
Does diode check OK?

Yes: F-Series, GO to «A7». Econoline, GO to «A13».
No: REPLACE diode.

A7 CHECK CIRCUIT 175 (BK/Y)
Measure resistance between nonpower side of diode connector Circuit 175 (BK/Y) to PCM relay connector.
Is resistance less than 5 ohms?

Yes: GO to «A8».
No: REPAIR open in Circuit 175.

A8 CHECK GROUND CIRCUIT 57 (BK) AT RELAY
Key off.
Measure resistance between battery negative to Circuit 57 (BK) at PCM relay connector.
Is resistance less than 5 ohms?

Yes: GO to «A9».
No: REPAIR open in Circuit 57 (BK).

A9 CHECK CIRCUIT 361 (R) FROM RELAY TO PCM
Disconnect PCM and inspect for damaged or pushed-out pins, corrosion, loose wires, etc. Service as necessary.
Measure resistance between Circuit 361 (R) at PCM relay connector to Test Pins 71 and 97.
Is resistance less than 5 ohms?

Yes: GO to «A10».
No: REPAIR open in Circuit 361 (R) between relay and PCM.

A10 CHECK PWR GND CIRCUIT CONTINUITY
Key off.
Install breakout box. Leave PCM disconnected. Inspect for damaged or pushed-out pins.
Measure resistance between battery negative post and Test Pins 25, 51, 76, 77 and 103 at the breakout box.
Is each resistance less than 5.0 ohms?

Yes: F-Series, GO to «A11». Econoline, GO to «A14».
No: SERVICE open in PWR GND circuit. REMOVE breakout box. RECONNECT PCM. RERUN Scan Tool Diagnostic Test.

A11 CHECK PCM RELAY
Key off.
Disconnect maxi fuse 9.
Install PCM relay.
Breakout box install, PCM disconnected.
Key on, engine off.
Measure resistance between nonpower side of maxi fuse 9 to Test Pins 71 and 97.
Is resistance less than 5 ohms?

Yes: If fault is still present, REPLACE PCM.
No: REPLACE PCM relay.

A12 CHECK VOLTAGE AT PCM RELAY
Key off.
Remove PCM relay from power distribution box.
Measure voltage at PCM relay connector Circuit 37 (Y) to battery negative.
Is battery voltage present?

Yes: GO to «A5».
No: REPAIR open in Circuit 37 (Y) between PCM relay and starter relay.

A13 CHECK CIRCUIT 16
Key off.
Measure resistance between nonpower side of diode connector Circuit 16 (R/LG) to PCM relay connector.
Is resistance less than 5 ohms?

Yes: GO to «A8».
No: REPAIR open in Circuit 16 (R/LG) between diode and relay.

A14 CHECK PCM RELAY
Key off.
Breakout box installed.
PCM disconnected.
PCM relay installed.
Key on.
Measure voltage between battery negative post to Test Pins 71 and 97.
Is battery voltage present?

Yes: If fault is still present, REPLACE PCM.
No: REPLACE PCM relay.
 
  #47  
Old 02-05-2013, 07:19 PM
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Thanks for that , if the alternator craps out or can't keep up , the batts will eventually die .. Mine did not . OPs truck has plenty to start . (only possible if the batts are up to it )Without a battery charger , that will not happen if the alternator is gone , or the batts are not up to it .. Have at it .Logic is seemingly not part of your diagnostic procedure. Now that you have mucked up OP's thread with your ego , I hope you can help him get it going ...
 
  #48  
Old 02-05-2013, 07:40 PM
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Originally Posted by kupiec20
how about that low voltage thing.
only asking because i just went out to start it and it wont start but its giving me a slow crank time.
its always turned over without any problem.
could it be related to my truck stalling?
This post is where I'm questioning the battery's and where my "ego" comes from , obviously you missed this post ...
 
  #49  
Old 02-05-2013, 07:46 PM
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Originally Posted by Action4478
I guess some of the fuel warms up over night .
Ego certainly didn't come into play here , oh certainly not .
Personally I do this for a living an have a lot of experience with these trucks . People alway look at the hard and technical stuff and disregard basic automotive musts.
Ego ? Yeah right
 
  #50  
Old 02-05-2013, 07:52 PM
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having fun.....lol
taking the batts out tomrw morning and ill get back to the tread. good night!
 
  #51  
Old 02-05-2013, 08:14 PM
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Originally Posted by Twistedwrench
Ego certainly didn't come into play here , oh certainly not .
Personally I do this for a living an have a lot of experience with these trucks . People alway look at the hard and technical stuff and disregard basic automotive musts.
Ego ? Yeah right
No logic , no ego ... Sorry OP .... twisted ,I feel sorry for your customers .
 
  #52  
Old 02-05-2013, 08:26 PM
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is OP me???
 
  #53  
Old 02-05-2013, 08:28 PM
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which batts are my best bang for my buck?
 
  #54  
Old 02-05-2013, 08:36 PM
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You'll want to have yours tested before you toss in new ones but , you'll want to get the highest rated cold cranking amp battery's that will fit in the battery tray . Group 65 is stock , group 34 will fit also . You'll want to grab a CPS too while you're out .
Action ; truce ?
I was wrong to start a fight , kupiec20 I apologize too
 
  #55  
Old 02-05-2013, 08:47 PM
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Originally Posted by Twistedwrench
Action ; truce ?
I was wrong to start a fight , kupiec20 I apologize too
Fair enough, I'll butt out my friend .Truce ...
 
  #56  
Old 02-05-2013, 08:52 PM
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Originally Posted by Action4478
Fair enough, I'll butt out my friend .Truce ...
No I can , I feel like a jerk now lol
 
  #57  
Old 02-05-2013, 09:02 PM
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Originally Posted by Twistedwrench
No I can , I feel like a jerk now lol
You shouldn't .. Take care of OP ..
 
  #58  
Old 02-05-2013, 09:06 PM
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ya lets get me running....nice to see all getting along.
im on the clock. big storm due fri morning.
 
  #59  
Old 02-05-2013, 09:08 PM
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You have 2 running PSD's right? Swap the batteries from the running truck to the broke one and see if that fixes it. Then you'll know.
 
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Old 02-05-2013, 09:11 PM
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Originally Posted by FI460
You have 2 running PSD's right? Swap the batteries from the running truck to the broke one and see if that fixes it. Then you'll know.
Good idea !
 


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