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In need of help please. I have a 2003 tl-s that is crank no start. New cam and crank sensors. Three different pgm relays. New ecu with immobilizer and key. Has no codes. Fuel pump comes on. No spark.
Here is a link to the manual. You mentioned you replaced the CAM and Crank sensors, did you replace the timing belt? Was the car starting before you did the replacements?
Sorry I did not see the other post. The car was a crank no start when I bought it. The car is in time with good compression. Engine is in time with new crank and cam sensors. No codes. Power and ground to coils. Fuel pump comes on. Tach does not display rpms while cranking.
There is no valve for fuel. There are two fuel rails. One has a regulator at one end and a pulsation damper where the fuel line come into the fuel rails. Check the manual.
Check page 4-15 of the manual and you can see the power for spark comes from the ignition to a 15A fuse under the dash (#11) and then to the coils. The coils need pulsed by the PCM if the PCM isn't there or isn't powered there will be no spark. The PCM gets it's power from the PGM main relay. Check to see if the PCM is there and powered. If the PCM is bad there could be no tach, it computes the speed from the crankshaft position sensor, there would also be no spark.
The pcm is there. I can read codes and it has none. It has fuel to the rails. I’m pretty sure the injectors are not firing either. I have tried pcm reset as well.
The only codes you might be able to see is if they were stored codes. The OBDII system only reads stored codes; unless the car is running. In your case it is not proof that the PCM is working. Have you downloaded the manual?
Yes I have downloaded the manual. Thanks for that. I read through it but didn’t see anything to help me I feel like. Like I said. It has no spark no injector pulse no rpm on gauge.
Go to the manual, search for DTC there is a troubleshooting procedure for not stating. Since your have seem to have a good battery, you need to move step by step and the manual contains EVERYTHING. It will not tell you what your problem is, it will tell you how to test things and what they do (you have to think about what they say and how it applies to your circumstance). There are multiple sections for troubleshooting and for no start you should check the PGM circuit, use page 11-160 to start, after checking the fuse in the diagram below. If the fuse is OK measure the voltage it should be battery voltage voltage and the battery should be at least 12.6 vDc. Check this fuse with a DVM. ALWAYS use a DVM to measure a fuse, I have seen fuses measure 100k ohms with no indication it was blown. All fuses should be 0 ohms.
Additionally the diagram below is the whole ignition circuit (page 4-15). Take a look at page 4-9.
Trace the voltage to the coils, make sure the ground by the starter is good, actually feel and look closely. If all is there then the inputs from the PCM are missing and you will need to try to capture the pulses on a DVM or O'scope.
The pulses are only there when you crank the Engine and the PCM is good.
I am not sure the diagrams are drawn to detail and I don't know if a resistor is in line I am not totally sure of what the voltage should be. However according to the diagrams there should be 12v at the fuse. According to the table below the blue/org wire should have battery voltage. The way I would proceed is to measure the voltage coming off the ignition switch (blk/wht wire) it should be 12 vDc. If so I would replace the starter cut relay. If the voltage is not 12v on blk/wht wire I would replace the ignition switch. One more question, does the green key indicator on the dash come on and go out when you turn the key to the on position?
Look at pages 22-190,191 etc. Unfortunately they don't tell you the expected voltage but I would expect 12v. I would replace the ignition switch. Those pages I just mention have additional tests.
Hopefully others will chime in here but if I remember correctly (and you can search the forum) several people have had problems with the switch.
I assume the immobilizer was not out. As I was recently reminded in another thread, by Whitetiger 5, if the transmission range switch is not aligned properly the car will not start. Search the PDF manual for the Transmission Range Switch. You can rotate the control arm shaft a bit each way. If the car doesn't think it is park or neutral the car won't start. 2nd page. pages 14-383,384
I am a little confused as you said the blu/ org wire had 5 volts yet now you had battery voltage between the fuse and ground. Electrically these are the same points so you must be measuring them differently. For example if you are measuring the voltage at the fuse on side other than side that the wire goes to the PGM relay and PCM. Or you measured the voltage at the fuse with the blu/org wire cut . So there are two possibilities I see with the information so far:
1. The fuse is partially blown. Did you measure across the fuse with an Ohmmeter (on ohms, key out)?
2. The PCM or PGM Main relay or something connected to them, has a partial short and causing the voltage to drop. The battery would be trying to supply the 12v at X current, with a partial short (damaged part) the battery would be trying to supply the 12v but the current demands (now XX) of the short are too much for the battery and the voltage it can provide will decrease.
I am still not sure what piece you replaced for the ignition. It should have been the part below (#8 or the entire assembly #1 or #2) Measure the voltage on the Black/ White wire coming from the ignition switch going to the fuse box. Then pull the #13 fuse and remeasure, both measurements need the key being turned all the way on. Record both voltages. If it is battery voltage when the fuse is removed then the ignition switch is Ok. If it is 5v when the fuse is removed then the ignition is bad. If it is 12v when the fuse is removed and 5v when the fuse is put back then something has gone resistive and the problem is 1 or 2 above.
04-11-2024, 08:20 PM
