Alfiedagr8
forum member
ok i wrote this up. i would like any input. hopfully we can improve this. if not we can always junk it..LOL.. let me know what you all think. i would like some feed back if you happen to use it.. worked or not. if i missed something that can cause a no start let me know i can add it somewhere..
Crank no start guide.
This guide will assume you have a good battery.
This guide is made for the poor man and only a test light and multi-meter are required.
Make sure you have inspected your vehicle engine harness for damage, possible chafing areas. Also if you have an aftermarket alarm make sure this is not causing your no start issues.
Side note: 10k ohms is the same as an open (OFL) reading.
Added step. Check for power on pin 13 on the DLC. Is there power present?
Yes-repair the cross short.
No-proceed with the guide.
Added step. For cars with two cam position sensors. Make sure that cmp1 and cmp2 circuits are not shorted together. Use a muli-meter with PCM connector disconnected. Measure resistance between all four pins, should be greater than 10k ohms.
CNS1-is there a theft light blinking rapidly?
Yes- PATS issues, recommend to take to a dealer
No- go to next step.
CNS2-does the car start with the MAF disconnected?
Yes. Possible damages MAF, clean and retest. Replace is necessary.
No. go to next step.
CNS3-does your instrument cluster have an odometer reading or dashes?
Dashes-the pcm is not communicating with ic. Go to step CNS16
Yes- odometer reading is good-go to next step
CNS4-(EEC V only 2005+ cars proceed to next step) does the car start while holding the car at part throttle?
Yes. IAC maybe be sticking, remove and inspect. Clean/replace as necessary.
No. go to next step.
CNS5- Check for proper fuel pressure. This can be done with a scan tool. Since this procedure is made not to use fancy tools. Lets check for fuel pump operation. Can you hear the fuel pump kick on while the key is moved to the on position (were on the dash lights kick on, not cranking). If your not sure and don’t mind a mess you may disconnect a fuel line and see if fuel shots out. Just be careful when you do this.
Note: you can also use some brake cleaner and shot some in the intake tube while cranking the motor and see if the car starts. If it starts then its fuel related. Answer NO in this case.
Yes-go to next step
No- go to step CNS21
CNS6-check for power to the injectors and coils, do you have battery voltage to the injectors and coils?
Yes- go to next step
No- check fuses. Check them all. Also test the PCM power relay.
CNS7-Check for injector pulse width. Do you have pulse width? (use a test light)
Yes-your engine is in sync. Check fuel sample. If no concern found then take to a dealer. This problem is beyond this guide.
No-go to next step
CNS8-Lets check for proper RPM signal. To do this, turn the key to the on position but do not crank the motor over. This will prime the fuel system. Once the fuel pump shuts off, Break a line open of the fuel system but leave the key on the ON position. Then crank the motor but going from the on position to the crank position. If the PCM sees a RPM signal from the CKP the fuel pump will kick on again. Does the fuel pump kick on while cranking?
Yes-this problem is beyond this guide.
No-put the car back together and go to next step. (you May also put a ckp sensor in it now and see if it fixes it.)
CNS9-Check or CKP sensor resistance. Specs is 250 ohms -1K ohms. Is the sensor within specs?
Yes- go to next step
No-replace ckp sensor and retest.
CNS10-Check for power on CKP+ and CKP- on the harness side to ground. Is voltage between 1v-3v?
Yes-go to next step.
No-go to step CNS12
CNS11-check the CKP harness shield ground. The harness shield protects the CKP signal from electrical noise and is grounded at one end, typically near the PCM. Carry out the following resistance measurement between the CKP shield and the chassis ground. Is resistance less than 5 OHMS?
Yes-go next step.
No- REPAIR the open circuit. CHECK for a poor ground connection
CNS12-check for cross shorts in the CKP circuit harness. Disconnect the pcm connector and check for resistance between ckp+ and ckp- harness side. Is the resistance greater than 10k ohms?\
Yes-go to next step
No-repair short
CNS13- check for open circuit in the ckp harness. Measure the resistance between the pcm and CKP sensor. Is resistance less than 5 ohms?
Yes-go to next step
No- repair circuit
CNS14-Check for short to ground in the ckp harness. Measure resistance between ckp- and ckp+ to ground. Is resistance greater than 10k ohms?
Yes-go to next step
No-repair short circuit
CNS15- with the pcm connector disconnected. Measure for voltage between ckp- and ckp+ to ground. Is there any voltage present?
Yes-repair short to power in the harness.
No- could be a faulty PCM recommend to take to a dealer
CNS16-check fuses to the pcm and pcm power relay. Do they test good?
Yes-go to next step.
No-repair as necessary
CNS17-check power and ground to the pcm. The pcm has multi power pins and ground. Check them all.
Are all power and ground circuits are good?
Yes- go to next step
No-repair as necessary.
CNS18-disconnect the ABS module. Does the car start now?
Yes-possible issue with the abs module.
No-go to next step.
CNS19-if you have a hand scanner or any scanner. Disconnect the IC and see if you can read pids off the PCM.(if you don’t have a scanner answer no. this rarely happens)
Yes-possible issue with the IC, take to a dealer for proper testing.
No-IC is not causing the pcm to shut down.
CNS20-check for shorted V-ref. there is a lot of vref circuits. I would disconnect every vref sensor there is. EOT,ECT, FRPS, FTPS, MAF, TPS, ETP, etc.. some cars have the ac pressure switch with v ref. make sure you get them all or get a wiring diagram to make sure.. you can also pull the pins out of the pcm connector. Pull the Vref feed pins. Does the car start now? Or can you read pids from the pcm?
Yes-find which sensor by trying one at a time. And replace.
No-possible PCM issue.
CNS21-c heck the IFS. Hit the button . does the car start?
Yes- road test and make sure its all ok.
No-go to next step.
CNS22-check power to the fuel pump its self. Do you get power to the fuel pump when turning the key to the on position?
Yes-replace fuel pump
No- go to next step
CNS23-check power and ground to the FPDM. Also check the wires from the PCM to the FPDM. Are the circuits good?
Yes-possible FPDM bad.
No-no repair as necessary.
Crank no start guide.
This guide will assume you have a good battery.
This guide is made for the poor man and only a test light and multi-meter are required.
Make sure you have inspected your vehicle engine harness for damage, possible chafing areas. Also if you have an aftermarket alarm make sure this is not causing your no start issues.
Side note: 10k ohms is the same as an open (OFL) reading.
Added step. Check for power on pin 13 on the DLC. Is there power present?
Yes-repair the cross short.
No-proceed with the guide.
Added step. For cars with two cam position sensors. Make sure that cmp1 and cmp2 circuits are not shorted together. Use a muli-meter with PCM connector disconnected. Measure resistance between all four pins, should be greater than 10k ohms.
CNS1-is there a theft light blinking rapidly?
Yes- PATS issues, recommend to take to a dealer
No- go to next step.
CNS2-does the car start with the MAF disconnected?
Yes. Possible damages MAF, clean and retest. Replace is necessary.
No. go to next step.
CNS3-does your instrument cluster have an odometer reading or dashes?
Dashes-the pcm is not communicating with ic. Go to step CNS16
Yes- odometer reading is good-go to next step
CNS4-(EEC V only 2005+ cars proceed to next step) does the car start while holding the car at part throttle?
Yes. IAC maybe be sticking, remove and inspect. Clean/replace as necessary.
No. go to next step.
CNS5- Check for proper fuel pressure. This can be done with a scan tool. Since this procedure is made not to use fancy tools. Lets check for fuel pump operation. Can you hear the fuel pump kick on while the key is moved to the on position (were on the dash lights kick on, not cranking). If your not sure and don’t mind a mess you may disconnect a fuel line and see if fuel shots out. Just be careful when you do this.
Note: you can also use some brake cleaner and shot some in the intake tube while cranking the motor and see if the car starts. If it starts then its fuel related. Answer NO in this case.
Yes-go to next step
No- go to step CNS21
CNS6-check for power to the injectors and coils, do you have battery voltage to the injectors and coils?
Yes- go to next step
No- check fuses. Check them all. Also test the PCM power relay.
CNS7-Check for injector pulse width. Do you have pulse width? (use a test light)
Yes-your engine is in sync. Check fuel sample. If no concern found then take to a dealer. This problem is beyond this guide.
No-go to next step
CNS8-Lets check for proper RPM signal. To do this, turn the key to the on position but do not crank the motor over. This will prime the fuel system. Once the fuel pump shuts off, Break a line open of the fuel system but leave the key on the ON position. Then crank the motor but going from the on position to the crank position. If the PCM sees a RPM signal from the CKP the fuel pump will kick on again. Does the fuel pump kick on while cranking?
Yes-this problem is beyond this guide.
No-put the car back together and go to next step. (you May also put a ckp sensor in it now and see if it fixes it.)
CNS9-Check or CKP sensor resistance. Specs is 250 ohms -1K ohms. Is the sensor within specs?
Yes- go to next step
No-replace ckp sensor and retest.
CNS10-Check for power on CKP+ and CKP- on the harness side to ground. Is voltage between 1v-3v?
Yes-go to next step.
No-go to step CNS12
CNS11-check the CKP harness shield ground. The harness shield protects the CKP signal from electrical noise and is grounded at one end, typically near the PCM. Carry out the following resistance measurement between the CKP shield and the chassis ground. Is resistance less than 5 OHMS?
Yes-go next step.
No- REPAIR the open circuit. CHECK for a poor ground connection
CNS12-check for cross shorts in the CKP circuit harness. Disconnect the pcm connector and check for resistance between ckp+ and ckp- harness side. Is the resistance greater than 10k ohms?\
Yes-go to next step
No-repair short
CNS13- check for open circuit in the ckp harness. Measure the resistance between the pcm and CKP sensor. Is resistance less than 5 ohms?
Yes-go to next step
No- repair circuit
CNS14-Check for short to ground in the ckp harness. Measure resistance between ckp- and ckp+ to ground. Is resistance greater than 10k ohms?
Yes-go to next step
No-repair short circuit
CNS15- with the pcm connector disconnected. Measure for voltage between ckp- and ckp+ to ground. Is there any voltage present?
Yes-repair short to power in the harness.
No- could be a faulty PCM recommend to take to a dealer
CNS16-check fuses to the pcm and pcm power relay. Do they test good?
Yes-go to next step.
No-repair as necessary
CNS17-check power and ground to the pcm. The pcm has multi power pins and ground. Check them all.
Are all power and ground circuits are good?
Yes- go to next step
No-repair as necessary.
CNS18-disconnect the ABS module. Does the car start now?
Yes-possible issue with the abs module.
No-go to next step.
CNS19-if you have a hand scanner or any scanner. Disconnect the IC and see if you can read pids off the PCM.(if you don’t have a scanner answer no. this rarely happens)
Yes-possible issue with the IC, take to a dealer for proper testing.
No-IC is not causing the pcm to shut down.
CNS20-check for shorted V-ref. there is a lot of vref circuits. I would disconnect every vref sensor there is. EOT,ECT, FRPS, FTPS, MAF, TPS, ETP, etc.. some cars have the ac pressure switch with v ref. make sure you get them all or get a wiring diagram to make sure.. you can also pull the pins out of the pcm connector. Pull the Vref feed pins. Does the car start now? Or can you read pids from the pcm?
Yes-find which sensor by trying one at a time. And replace.
No-possible PCM issue.
CNS21-c heck the IFS. Hit the button . does the car start?
Yes- road test and make sure its all ok.
No-go to next step.
CNS22-check power to the fuel pump its self. Do you get power to the fuel pump when turning the key to the on position?
Yes-replace fuel pump
No- go to next step
CNS23-check power and ground to the FPDM. Also check the wires from the PCM to the FPDM. Are the circuits good?
Yes-possible FPDM bad.
No-no repair as necessary.
