1999 GMC Jimmy Repair Question
You have fuel but are the injectors pulsing?
Are you getting ignition sparks?
Did you check for trouble codes?
i do her the injecotrs, yes i checked the spark andm i habe not checked for codes yet, but i really would like to know if the two wires for the coolant remp sensor should be getting power when the igniton is on?
One of the wire should have a 5 volt with ignition turned on.
i pulled the codes and got P1351, 1.Ic circuit high voltage, 2.ic circuits 1 & 4 malfunction....
Which engine do you have?
Check out the diagnostic procedures.
DTC P1351: IGNITION CONTROL (IC) CIRCUIT HIGH VOLTAGE
Crankshaft Position (CKP) sensor provides VCM with reference pulse input. VCM uses CKP input to determine ignition spark timing for each cylinder. Once VCM calculates ignition timing, it sends a signal to ignition coil module on IC circuit. DTC will set when IC voltage is greater than 4.9 volts.
1. Perform On-Board Diagnostic (OBD) system check. After performing
OBD system check, go to next step.
2. Clear DTCs. Disconnect fuel injector connector. Crank engine for 15 seconds. Read DTCs. If this DTC resets, go to next step. If this DTC does not reset, see DIAGNOSTIC AIDS.
3. Turn ignition off. Reconnect fuel injector connector. Disconnect ignition coil module connector. Using DVOM in AC scale, check voltage between engine ground and IC control circuit at ignition coil module, while cranking engine. If voltage reading is 1-4 volts, go to step 9. If voltage reading is not 1-4 volts, go to next step.
4. Turn ignition off. Disconnect VCM harness connector. Check for open in IC control circuit between VCM harness connector terminal No. 9 and ignition coil module harness connector terminal "B". If circuit is open, go to next step. If resistance is not open, go to step 6.
5. Repair open IC control circuit between VCM and ignition coil module. After repairs, go to step 17.
6. Reconnect VCM harness connector. Turn ignition on, with engine off. Check voltage between ground and ignition control module harness connector terminal "B". If voltage reading is greater than one volt, go to next step. If voltage reading is not greater than one volt, go to step 8.
7. Repair short to voltage in IC control circuit between VCM and ignition control module. After repairs, go to step 17.
8. Check for poor VCM harness connections. If connections are faulty, go to step 15. If connections are okay, go to step 16.
9. Turn ignition off. Connect a test light between battery voltage and ignition coil module harness connector ground circuit. If test light illuminates, go to step 11. If test light does not illuminate, go to next step.
10. Repair open ignition coil module ground circuit. After repairs, go to step 17.
11. Turn ignition on. Connect test light between engine ground and ignition coil module harness connector ignition feed circuit, and then ignition coil module harness connector tachometer signal circuit. If test light illuminates on both circuits, go to step 13. If test light does not illuminate on both circuits, go to next
12. Repair faulty circuit. After repairs, go to step 17.
13. Check for poor connection at ignition coil module. If connection is faulty, go to step 15. If connection is okay, go to next step.
14. Replace ignition coil module. After replacing module, go to step
15. Repair faulty connection. After repairs, go to next step.
16. Replace VCM. Program replacement VCM using required equipment. After replacing VCM, go to next step.
17. Using scan tool, select DTC, CLEAR INFO function. Start engine and allow it to reach operating temperature. Using scan tool, select DTC, SPECIFIC function and enter this DTC. Operate vehicle within conditions required to set DTC. If scan tool indicates that this test RAN AND PASSED, go to next step. If scan tool does not indicate that this test RAN AND PASSED, repeat step 2.
18. Using scan tool, select Read and Record INFO, REVIEW INFO function. Check if any undiagnosed DTCs are displayed. Diagnose affected DTCs. If no additional DTCs are displayed, system is okay.
Check for faulty connections or damaged harness. If connections and harness appear okay, observe scan tool while moving all related harnesses and connectors. A change in scan tool display indicates fault location.
ok that will take awhile, thank you for helping, i will report back.
I replaced the Ignition Coil And Module But Still Wont Start, both ARE getting Power. Any more ideas ?
Why did you replace the ignition coil and module? Did you follow the test and tit said so?