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Home >> GMC >> 1991 >> Value Van 7.4 N >> Repair and Diagnosis >> External Pages >> Different car >> Section 24 (Engine Controls - Tests W/Codes - 2.5L) >> Self-Diagnostic Tests >> Test TC-2A - No Crank Reference Signal At Pcm (DTC 11)

Test TC-2A - No Crank Reference Signal At Pcm (DTC 11)

WARNING: This page is about a different car, the 1995 Dodge Dakota. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: For circuit and connector terminal identification, see CONNECTOR IDENTIFICATION . For wiring diagrams, see WIRING DIAGRAM  section.
  1. Erase DTCs using scan tool. Attempt to start engine. If engine will not start, crank engine for at least 10 seconds.
  2. Using scan tool, read DTCs. If scan tool displays NO CRANK REFERENCE SIGNAL AT PCM, go to step 6). If scan tool does not display NO CRANK REFERENCE SIGNAL AT PCM, condition required to set DTC message is not present at this time. Go to next step.
  3. NO CRANK REFERENCE SIGNAL AT PCM DTC sets if Powertrain Control Module (PCM) does not see a Crankshaft Position (CKP) sensor signal during cranking. Possible causes are: failed CKP sensor, open or shorted CKP sensor Gray/Black wire, open or shorted CKP sensor Orange wire, open CKP sensor Black/Light Blue wire, failed distributor drive, excessive clearance between sensor and rotor, damaged rotor, or failed PCM. Go to next step.
  4. Inspect all related wiring and connectors and repair as necessary. Perform TEST VER-2. If no problems are found with wiring and connectors, go to next step.
  5. Start engine. Wiggle wiring harness from CKP sensor to Powertrain Control Module (PCM). If engine misfires or stalls, repair wiring harness as necessary. Perform TEST VER-2. If engine does not misfire or stall, see INACTIVE DTC CONDITION. Perform TEST VER-2.
  6. Turn ignition off. Disconnect Crankshaft Position (CKP) sensor connector. Inspect CKP sensor connector for damaged or pushed-out terminals. Repair as necessary. Perform TEST VER-2. If sensor connector terminals are okay, go to next step.
  7. Turn ignition on. Put scan tool in voltmeter mode. Using scan tool, check voltage on CKP sensor connector Orange wire. If voltage is less than 7 volts, go to TEST TC-2B.
  8. If voltage is more than 7 volts, disconnect coil wire from distributor cap. Place end of coil wire 1/4" from ground. Connect a jumper wire between Gray/Black wire and Black/Light Blue wire on CKP sensor connector.
  9. Make and break connection at CKP sensor connector several times while watching coil wire for spark. If coil wire sparks, go to next step. If coil wire does not spark, go to step 11).
  10. Remove distributor cap. Crank engine while watching rotor. If rotor turns, replace CKP sensor. Perform TEST VER-2. If rotor does not turn, repair distributor drive system as necessary. Perform TEST VER-2.
  11. Turn ignition off. Put scan tool in ohmmeter mode. Check resistance on CKP sensor connector Black/Light Blue wire. If resistance is more than 5 ohms, repair open Black/Light Blue wire. Perform TEST VER-2.
  12. If resistance is less than 5 ohms, disconnect PCM connector. Inspect PCM sensor connector for damaged or pushed-out terminals. Repair as necessary. Perform TEST VER-2. If PCM connector terminals are okay, go to next step.
  13. Using an external ohmmeter, check resistance of Gray/Black wire between CKP sensor connector and PCM connector terminal No. 24. If resistance is more than 5 ohms, repair open Gray/Black wire. Perform TEST VER-2.
  14. If resistance is less than 5 ohms, put scan tool in ohmmeter mode. Check resistance of CKP sensor connector Gray/Black wire. If resistance is more than 5 ohms, replace PCM. Perform TEST VER-2. If resistance is less than 5 ohms, repair short to ground in Gray/Black wire. Perform TEST VER-2.
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