Another **Wont Start** **No Spark**
11-07-2008, 12:33 PM
#11
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Well I re-did the ground exactly how they are on our vehicles, and that has not worked for me. I still cannot get a spark when I crank the engine. I think the grounds are fine for the coils because when I test the ground which is connected just underneath the power steering pump I have continuity going from that ground to the coils. When I turn the ignition on I have power going to the pink wire on the coils.I have ground going to the coils (blk wire). I have a ground going to the coil (brown wire) when I turn the ignition on. And nothing happens to the green wire. But I tried to test this wire when I turn in the ignition on a truck that runs and nothing happens to this wire either.
So what the hell am I missing? How can I trouble shoot this thing? Here is a link to the coil schematic.
http://www.mazdamaniac.com/images/rx..._schematic.jpg
So what the hell am I missing? How can I trouble shoot this thing? Here is a link to the coil schematic.
http://www.mazdamaniac.com/images/rx..._schematic.jpg
11-07-2008, 01:57 PM
#12
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Electronic Ignition (EI) System Diagnosis
Circuit Description
The electronic ignition system uses an individual ignition coil for each cylinder. The powertrain control module (PCM) controls the ignition operation through eight individual ignition control (IC) circuits. Each bank of four ignition coils is connected to the PCM, power, or ground by the following circuits:
* Low reference
* Chassis ground
* Ignition 1 voltage
* The appropriate IC circuit
The PCM triggers an ignition coil by grounding the appropriate IC circuit using information from the crankshaft position (CKP) and camshaft position (CMP) sensors.
Important
A missing CMP sensor signal may cause a long crank condition.
The CKP signal must be available for the engine to start. The CMP signal is not needed to start and operate the engine. The PCM can determine when a cylinder is on either the firing or exhaust stroke by the 24X signal.
Remove any debris from the PCM connector surfaces before servicing the PCM. Inspect the PCM connector gaskets when diagnosing or replacing the PCM. Ensure that the gaskets are installed correctly. The gaskets prevent water intrusion into the PCM.
Attempt to start the engine.
1. Observe the Engine Speed parameter with a scan tool.
2. Crank the engine.
Does the scan tool indicate RPM is present?
1. Turn ON the ignition, with the engine OFF.
2. Disconnect the crankshaft position (CKP) sensor.
3. Measure the voltage from the CKP sensor 12-volt reference circuit and a good ground with the Digital Multimeter.
4. Compare the measured voltage with the system voltage.
Is the difference in the voltage more than the specified value? 0.5V
Circuit Description
The electronic ignition system uses an individual ignition coil for each cylinder. The powertrain control module (PCM) controls the ignition operation through eight individual ignition control (IC) circuits. Each bank of four ignition coils is connected to the PCM, power, or ground by the following circuits:
* Low reference
* Chassis ground
* Ignition 1 voltage
* The appropriate IC circuit
The PCM triggers an ignition coil by grounding the appropriate IC circuit using information from the crankshaft position (CKP) and camshaft position (CMP) sensors.
Important
A missing CMP sensor signal may cause a long crank condition.
The CKP signal must be available for the engine to start. The CMP signal is not needed to start and operate the engine. The PCM can determine when a cylinder is on either the firing or exhaust stroke by the 24X signal.
Remove any debris from the PCM connector surfaces before servicing the PCM. Inspect the PCM connector gaskets when diagnosing or replacing the PCM. Ensure that the gaskets are installed correctly. The gaskets prevent water intrusion into the PCM.
Attempt to start the engine.
1. Observe the Engine Speed parameter with a scan tool.
2. Crank the engine.
Does the scan tool indicate RPM is present?
1. Turn ON the ignition, with the engine OFF.
2. Disconnect the crankshaft position (CKP) sensor.
3. Measure the voltage from the CKP sensor 12-volt reference circuit and a good ground with the Digital Multimeter.
4. Compare the measured voltage with the system voltage.
Is the difference in the voltage more than the specified value? 0.5V
11-08-2008, 01:41 PM
#16
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I am asuming you are using a truck harness and fuse block. Hook your meter to read voltage on the fuse that powers the coils and crank the engine over. See if your voltage drops, If less than 9 volts, you are not getting enough voltage to your fuse. Not sure how your ignition switch is hooked up.
