12-14-2017, 01:53 AM
The following is a draft, sent to Popgun and Max (last week) for collaboration on possibly replacing MCS tests with multimeter only tests. Popgun has indicated that he is not able to start on it this month, so do not expect updates until January, 2018, at the earliest.
This is a condensed version of pages 5-17 through 5-20 of the FSM.
If anyone with a FSM notices any errors, please advise.
DTC 1-1 MAP (Manifold Absolute Pressure) sensor low voltage
Black/yellow wire (common to TPS) junctions to yellow/red to ECM A9
Light/green to ECM B28
Black/green junctions to green/orange to ECM A18
Step one
MCS test: With ignition one, stop/run on, check for ~0 vdc. If ~0 vdc, go to step 2. If not, diagnose intermittent failure.
Step 2
With MAP connector disconnected, ignition switch on, stop/run on, probe connector outside pins black/yellow (+) to black/green (-) for 4.75 to 5.25 vdc. If ~ 5 vdc, go to step 4. If not, go to step 3.
Step 3
Check continuity on black/yellow to ECM connector A9. If continuity (expect ohms =/< 0.1), replace ECM with known good and recheck. If no continuity, replace/repair black/yellow – yellow/red wire.
Step 4
With ignition off, check MAP output center pin light green/yellow wire for no continuity (infinity) to ground. If grounded, replace/repair light green/yellow wire. If not grounded, got to step 5.
Step 5
Replace MAP sensor with known good unit.
Clear the ECM self -diagnosis memory data. [Separate write-up to be developed]
With ignition on, stop/run on, is DTC 1-1 indicated? If yes, replace ECM. If not replace, MAP sensor.
DTC 1-2 MAP (Manifold Absolute Pressure) sensor high voltage
Step 1
MCS test: With ignition one, stop/run on, check for ~5 vdc. If ~5 vdc, go to step 2. If not, diagnose intermittent MAP failure.
Step 2
MCS test: With MAP disconnected, then ignition on, stop/run on, jumper black/green to light green/yellow (middle pin). If ~0 vdc, replace MAP. If not, go to step 3.
Step 3
With jumper removed and MAP connector still disconnected, ignition switch on, stop/run on, probe connector outside pins black/yellow (+) to black/green (-) for 4.75 to 5.25 vdc. If ~ 5 vdc, go to step 4. If not, replace/repair black/yellow – yellow/green wire or black/green – green/orange wire.
Step 4
With MAP connector still disconnected, ignition off, check for continuity from light green/yellow to B28. If continuity (expect ohms =/< 0.1), replace ECM with known good and recheck. If no continuity, replace/repair light green/yellow wire.
DTC 2-1 MAP sensor hose connection
Step 1
MCS test: With motor running, check MAP at idle. If reading changed, diagnose intermittent MAP failure. If not, go to step 2.
Step 2
Verify MAP sensor hose properly connected
Step 3
MCS test: Replace MAP sensor with known good unit. With motor running, check idle speed with MCS. If reading changed, replace MAP sensor. If not, replace ECM with known good unit and recheck.
This is a condensed version of pages 5-17 through 5-20 of the FSM.
If anyone with a FSM notices any errors, please advise.
DTC 1-1 MAP (Manifold Absolute Pressure) sensor low voltage
Black/yellow wire (common to TPS) junctions to yellow/red to ECM A9
Light/green to ECM B28
Black/green junctions to green/orange to ECM A18
Step one
MCS test: With ignition one, stop/run on, check for ~0 vdc. If ~0 vdc, go to step 2. If not, diagnose intermittent failure.
Step 2
With MAP connector disconnected, ignition switch on, stop/run on, probe connector outside pins black/yellow (+) to black/green (-) for 4.75 to 5.25 vdc. If ~ 5 vdc, go to step 4. If not, go to step 3.
Step 3
Check continuity on black/yellow to ECM connector A9. If continuity (expect ohms =/< 0.1), replace ECM with known good and recheck. If no continuity, replace/repair black/yellow – yellow/red wire.
Step 4
With ignition off, check MAP output center pin light green/yellow wire for no continuity (infinity) to ground. If grounded, replace/repair light green/yellow wire. If not grounded, got to step 5.
Step 5
Replace MAP sensor with known good unit.
Clear the ECM self -diagnosis memory data. [Separate write-up to be developed]
With ignition on, stop/run on, is DTC 1-1 indicated? If yes, replace ECM. If not replace, MAP sensor.
DTC 1-2 MAP (Manifold Absolute Pressure) sensor high voltage
Step 1
MCS test: With ignition one, stop/run on, check for ~5 vdc. If ~5 vdc, go to step 2. If not, diagnose intermittent MAP failure.
Step 2
MCS test: With MAP disconnected, then ignition on, stop/run on, jumper black/green to light green/yellow (middle pin). If ~0 vdc, replace MAP. If not, go to step 3.
Step 3
With jumper removed and MAP connector still disconnected, ignition switch on, stop/run on, probe connector outside pins black/yellow (+) to black/green (-) for 4.75 to 5.25 vdc. If ~ 5 vdc, go to step 4. If not, replace/repair black/yellow – yellow/green wire or black/green – green/orange wire.
Step 4
With MAP connector still disconnected, ignition off, check for continuity from light green/yellow to B28. If continuity (expect ohms =/< 0.1), replace ECM with known good and recheck. If no continuity, replace/repair light green/yellow wire.
DTC 2-1 MAP sensor hose connection
Step 1
MCS test: With motor running, check MAP at idle. If reading changed, diagnose intermittent MAP failure. If not, go to step 2.
Step 2
Verify MAP sensor hose properly connected
Step 3
MCS test: Replace MAP sensor with known good unit. With motor running, check idle speed with MCS. If reading changed, replace MAP sensor. If not, replace ECM with known good unit and recheck.