I am absolutely pulling my hair out and I am about to take it to a mechanic. I really enjoy working on my own rigs and until now have alway been able to repair my vehicles. This may have me stumped.
This is also a follow up to my recent thread Dealer Can't Connect to PCM.
I bought AE, hooked it up and had a boat load of codes. I have no idea how long it has been since they have been cleared. This was the original list of codes.
B1318 Battery Voltage Low
B1352 Ignitions Key in circuit Fault
P0500 Vehicle Speed Sensor A
U2015 Signal Link Fault (Non SCP)
P1280 Injector Control Pressure Sensor Circuit Low
P1670 Electronic Feedback Signal Not Detected
P0381 Glow Plug/Heater Indicator Circuit
P1139 Water in Fuel Indicator Circuit
I discovered I had a bad battery so I now have two brand new batteries.
It is getting fuel to the fuel bowl. I am not sure how much pressure but it has filled up the bowl a few times.
So I cleared the codes and turned it over. No start so that isn't the problem.
New codes after cranking:
P0500 Vehicle Speed Sensor A
U2015 Signal Link Fault(Non SCP)
P1670 Electronic Feedback Signal Not Detected.
Tried to run a KOEO test. Came back with P1668 PCM/IDM Communications Error
Tried to run a buzz test. Came back with same error.
While turning over AE had the following readings. (I love the log function)
Voltage was 12.1 before cranking. Looks to be 10.4v 10.3v while cranking. 11.1V after cranking. I am kind of concerned about the <10.5v with new batteries. They are on a charge and I will check them again.
ICP pressure 2300ish.
RPM 130-140.
Fuel Injector Pulse Width .38 (Added this one because I was curious.)
Since I am showing RPMs and ICP pressure I am ruling out the CPS and ICP...for now.
Then last night while muddling around trying to figure out what was going wrong, I stumbled across this website http://www.gbreman.com/ and the IDM testing procedure in the link.
I have tested each circuit as this diagram shows:
![]()
I am out of range from the values shown in test #1. Tests #2 and #3 are fine.
My values for test #1 are as follows:
23 - 22 = 7.8 Ohms
23 - 7 = 4.5 Ohms
23 - 19 =6.8 Ohms
23 - 9 = 6.8 Ohms
24 - 6 = 146k Ohms (This must be a short)
24 - 21 = 4.1 Ohms
24 - 8 = 2k Ohms (This must be a short)
24 - 20 = 62 Ohms
I can see that I need to follow back the right bank for sure. Does anyone have any thoughts on the other circuits that are out of spec based on the data shown? Heck, is the data even right?
If I do have a short, could this have ruined the IDM?
This is also a follow up to my recent thread Dealer Can't Connect to PCM.
I bought AE, hooked it up and had a boat load of codes. I have no idea how long it has been since they have been cleared. This was the original list of codes.
B1318 Battery Voltage Low
B1352 Ignitions Key in circuit Fault
P0500 Vehicle Speed Sensor A
U2015 Signal Link Fault (Non SCP)
P1280 Injector Control Pressure Sensor Circuit Low
P1670 Electronic Feedback Signal Not Detected
P0381 Glow Plug/Heater Indicator Circuit
P1139 Water in Fuel Indicator Circuit
I discovered I had a bad battery so I now have two brand new batteries.
It is getting fuel to the fuel bowl. I am not sure how much pressure but it has filled up the bowl a few times.
So I cleared the codes and turned it over. No start so that isn't the problem.
New codes after cranking:
P0500 Vehicle Speed Sensor A
U2015 Signal Link Fault(Non SCP)
P1670 Electronic Feedback Signal Not Detected.
Tried to run a KOEO test. Came back with P1668 PCM/IDM Communications Error
Tried to run a buzz test. Came back with same error.
While turning over AE had the following readings. (I love the log function)
Voltage was 12.1 before cranking. Looks to be 10.4v 10.3v while cranking. 11.1V after cranking. I am kind of concerned about the <10.5v with new batteries. They are on a charge and I will check them again.
ICP pressure 2300ish.
RPM 130-140.
Fuel Injector Pulse Width .38 (Added this one because I was curious.)
Since I am showing RPMs and ICP pressure I am ruling out the CPS and ICP...for now.
Then last night while muddling around trying to figure out what was going wrong, I stumbled across this website http://www.gbreman.com/ and the IDM testing procedure in the link.
I have tested each circuit as this diagram shows:
I am out of range from the values shown in test #1. Tests #2 and #3 are fine.
My values for test #1 are as follows:
23 - 22 = 7.8 Ohms
23 - 7 = 4.5 Ohms
23 - 19 =6.8 Ohms
23 - 9 = 6.8 Ohms
24 - 6 = 146k Ohms (This must be a short)
24 - 21 = 4.1 Ohms
24 - 8 = 2k Ohms (This must be a short)
24 - 20 = 62 Ohms
I can see that I need to follow back the right bank for sure. Does anyone have any thoughts on the other circuits that are out of spec based on the data shown? Heck, is the data even right?
If I do have a short, could this have ruined the IDM?