PcolaBeach
Cadet
- Joined
- May 26, 2019
- Messages
- 26
Good morning ... I'm hoping to receive input on this issue from the more experienced personnel within the Forum. Thank you to all in advance. I've read so many posts on various forums that simply ended without conclusion, one thing I will commit to is closing the loop on whatever the solution turns out to be.
The engine in question is:
Volvo Penta 5.7 GXi-C Raw Water Cooled
Serial Number 4012062213
Production Number 3869137
MEFI Assembly Number 57IAFM/02HT01 3861773
Boat - 2002 Cobalt 240
Symptoms:
1. DTC Code 81 is present - We don't have a scan tool. This was obtained via the paper clip and counts 1-2, then 8-1, then 1-2
2. Cranks fine off the starter motor but will not fire
3. Fuel Pumps do not go through their normal 2 sec prime / stop as ignition key is placed to on
4. Fuel Pumps do not operate during cranking
5. Will fire and idle well with an ounce or so of fuel added through throttle body
6. Audible alarm is a persistent, non-stopping on off on off, etc. once the key is in the on position regardless of what other action is being done
7. Boat has not run in 18 months - fuel in tank has been replaced
Actions taken:
1. Although batteries are 6 months old, batteries have both been recharged and read 12.6v dc
2. Prior to my involvement, ECM's were exchanged with a supposedly good one although I wasn't around during that testing
3. HP fuel pump has been replaced due to recommendation from a previous marine mechanic.
4. Fuel Pressure regulator removed, screen sprayed clean with carburetor cleaner
5. Batteries grounds all indicate less than 0.5 ohms
6. ECM grounds from J1 connector pins 13, 28, 29 all tested good at 0.2 ohms
7. Verified and tested all 5 15A & 20A fuses at relay terminal
8. Verified and tested fuel pump and ignition relays - 0.2 ohms with contacts closed
9. Continuity tested SB/Y wire from fuel pump relay terminal 85 to J1 connector pin 6 - 0.2 ohms
10. Continuity tested Y/GN fuel pump wiring from relay contact 87 to each pump harness connector - 0.3 ohms or so
11. Continuity tested SB fuel pump ground wiring - 0.3 ohms
12. Added clear tygon line to pump assembly, and at fuel pump relay terminals jumpered 30 to 87. Fuel Pumps each operated continuously until jumper was removed
13. 12v dc and a solid ground have been confirmed at both the crankshaft and camshaft sensor harnesses. Signal voltage from each sensor has not been confirmed as I did not have a sewing needle to back probe for this voltage.
Over the last several weeks, I've been helping a friend troubleshoot several items on this engine. Although many hours have been spent trying to find something of a scenario comparable within the VP Forum, I've not quite been successful. I've been using Workshop Manual C EFI Diagnostic 2(0) for troubleshooting logic as well as the appropriate wiring diagram. I'm not a Marine Mechanic although I spent a career managing electrical power plants using aero-derivative engines as the prime mover for power production and enjoy this type of troubleshooting on EFI auto engines.
Given the symptoms and testing described above, it's my opinion the fuel pump relay ground at J1 pin 6 is not being commanded closed to ground by the ECM. That being said, I don't know if this is because of a "problem" with the ECM or a separate permissive issue the ECM is sensing that results in the ECM electing to not complete the ground circuit for J1 pin 6 to FP Relay contact 85. I do appreciate the extra sets of eyes and knowledge. Thank you!
The engine in question is:
Volvo Penta 5.7 GXi-C Raw Water Cooled
Serial Number 4012062213
Production Number 3869137
MEFI Assembly Number 57IAFM/02HT01 3861773
Boat - 2002 Cobalt 240
Symptoms:
1. DTC Code 81 is present - We don't have a scan tool. This was obtained via the paper clip and counts 1-2, then 8-1, then 1-2
2. Cranks fine off the starter motor but will not fire
3. Fuel Pumps do not go through their normal 2 sec prime / stop as ignition key is placed to on
4. Fuel Pumps do not operate during cranking
5. Will fire and idle well with an ounce or so of fuel added through throttle body
6. Audible alarm is a persistent, non-stopping on off on off, etc. once the key is in the on position regardless of what other action is being done
7. Boat has not run in 18 months - fuel in tank has been replaced
Actions taken:
1. Although batteries are 6 months old, batteries have both been recharged and read 12.6v dc
2. Prior to my involvement, ECM's were exchanged with a supposedly good one although I wasn't around during that testing
3. HP fuel pump has been replaced due to recommendation from a previous marine mechanic.
4. Fuel Pressure regulator removed, screen sprayed clean with carburetor cleaner
5. Batteries grounds all indicate less than 0.5 ohms
6. ECM grounds from J1 connector pins 13, 28, 29 all tested good at 0.2 ohms
7. Verified and tested all 5 15A & 20A fuses at relay terminal
8. Verified and tested fuel pump and ignition relays - 0.2 ohms with contacts closed
9. Continuity tested SB/Y wire from fuel pump relay terminal 85 to J1 connector pin 6 - 0.2 ohms
10. Continuity tested Y/GN fuel pump wiring from relay contact 87 to each pump harness connector - 0.3 ohms or so
11. Continuity tested SB fuel pump ground wiring - 0.3 ohms
12. Added clear tygon line to pump assembly, and at fuel pump relay terminals jumpered 30 to 87. Fuel Pumps each operated continuously until jumper was removed
13. 12v dc and a solid ground have been confirmed at both the crankshaft and camshaft sensor harnesses. Signal voltage from each sensor has not been confirmed as I did not have a sewing needle to back probe for this voltage.
Over the last several weeks, I've been helping a friend troubleshoot several items on this engine. Although many hours have been spent trying to find something of a scenario comparable within the VP Forum, I've not quite been successful. I've been using Workshop Manual C EFI Diagnostic 2(0) for troubleshooting logic as well as the appropriate wiring diagram. I'm not a Marine Mechanic although I spent a career managing electrical power plants using aero-derivative engines as the prime mover for power production and enjoy this type of troubleshooting on EFI auto engines.
Given the symptoms and testing described above, it's my opinion the fuel pump relay ground at J1 pin 6 is not being commanded closed to ground by the ECM. That being said, I don't know if this is because of a "problem" with the ECM or a separate permissive issue the ECM is sensing that results in the ECM electing to not complete the ground circuit for J1 pin 6 to FP Relay contact 85. I do appreciate the extra sets of eyes and knowledge. Thank you!