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Update – I replace crankshaft sensor, camshaft sensor, and checked the wires. Mechanic said that I need a new ECU. I’ve been browsing and can’t find an exact match part number. (I can find a match to the top number, but not the bottom)
Does anyone know what the bottom number means, or if I need to find an exact match? I can match the top but not the bottom:
My part number is
37820-PLM-L54
2415-332155——————————————————-
My 2002 Civic lx decided to stop working today. I lost acceleration, and the check engine light came on. I rode for half a mile at a very slow speed. There may or may not have been a little smoke coming from my engine/radiator.. I waited a little while, and then I drove up to the gas station slowly, and got some oil because I was a little low. After adding oil, the car drove fine (I inspected the bottom to find that no oil was leaking out)
I got my codes checked, and they have nothing to do with oil. It drove about 20 miles, then I stopped to grab something from the store, and it was giving very limited power. I turned it off for a second, and then it cranked and drove fine for another 10 miles.. Now, when I turn my car back on it has trouble staying on, and will barely drive. I can’t get up the street, and I really don’t know why..My codes:
P1298
Electric load detector (ELD) circuit high inputP1361
intermittent interruption in TDC 1 sensor circuitSo do I just need a new ELD, and a Camshaft position sensor, or does this problem mean something else?
someone told me TDC could be crankshaft position sensor, and others say it is cam shift sensor.. which one is it, or both?I ordered ELD and CamShaft sensor, because they are not carried in my local part stores.
Thanks
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The TDC sensor goes by several names, including crankshaft angle sensor and crankshaft position sensor. The computer uses this sensor to determine where the crankshaft is for engine timing and other management tasks. It is not the same as a camshaft sensor. TDC means “top dead center” and refers to the position of the crankshaft. It is common that these get contaminated with oil and dirt without actually failing. I would first remove, clean, and reinstall the existing sensor before replacement. Many good sensors have been thrown in the trash due to poor diagnostic practices. That isn’t to say that yours didn’t actually fail. However, I always like to KNOW I need it before I swap it, whatever ‘it’ may happen to be. Saves lots of dollars, too.
As for the ELD, it could have been an intermittent fault. It can sometimes be caused by a wiring problem in the harness rubbing on the intake manifold. Check your fuses and wiring. Clear the computer, and see if it comes back.
Thank you for your response
people are mixing up Crankshaft sensor and Camshaft sensor, so I will probably have to check both
[IMG]http://lapload.com/image.uploads/15-03-2015/original-1c2ec651619cb05a18813db54d882dc5.jpg[/IMG]I checked fuses, and they seemed fine. I reset the ECU and it still will barely work.( I do not have an OBD II reader to see if I have both codes, or just 1, after resetting)
Yes, sensor nomenclature can be fun. Especially on cars that have both cam and crank sensors, because both could be called TDC depending on perspective. I prefer to reference them as crank or cam sensors, to eliminate any ambiguity. Technically speaking, the term ‘top dead center’ refers to the position of a piston in the cylinder, and that is determined by the crankshaft. For timing purposes, though, TDC occurs twice, at the end of compression stroke, and end of exhaust stroke. Depending on what the needs of the computer are seems to determine the names of the sensors it uses.
Update – I replace crankshaft sensor, camshaft sensor, and checked the wires. Mechanic said that I need a new ECU. I’ve been browsing and can’t find an exact match part number. (I can find a match to the top number, but not the bottom)
My part number is37820-PLM-L54
2415-332155What does the second/lower number mean?
Thank you
So, that means one of two things … 1) All the sensors that you replaced were probably not bad, and if they were tested properly before replacement, it would have revealed they didn’t need to be replaced. Money wasted. 2) You are (again) taking someone’s word that you need to swap a part. Computers can be tested also. There are manuals and books for this. What happens when you swap ECUs and it still doesn’t fix the problem? Money wasted. The bottom line, sensors and computers do fail and need replacement now and again. But, it is far more important for you, to know what needs to be replaced through proper diagnostic and not just swap out a part through trial and error until the problem goes away. As for your part number, the bottom part is most likely a factory manufacture code, like date/time/lot number, and is meaningless for part replacement.
You have not said whether the check engine light is constantly flashing while the engine is running. You have not indicated if you have had the alternator tested. You have not mentioned whether you have checked all the engine and body ground points for loose or corroded connections. These are all things to test before swapping out a potentially expensive computer.
I was reflecting on my previous reply, and felt it may have come across a little harsh. I wanted to reassure you, and others interested in this topic, that I wasn’t trying to scold you or anything. Along with the others here, I share my experience and advice in order to help you fix your car with the most accurate diagnosis possible and the least amount of money spent, given that we are all on the other side of the internet from you and cannot access your vehicle.
That being said, let’s go one step further on my previous reply. Suppose your ECM has gone bad and does in fact need to be replaced. Ok. Easy fix. Or it is? They don’t usually just go bad. There is nearly always a reason it went bad, and without knowing that reason and correcting it, you could be replacing it again soon. Why did I mention those other tests in my previous reply? I did mention 2 weeks ago to check all the fuses and all the wiring (meaning opens, shorts, and engine and body grounds). Alternators have internal electronics that can get contaminated with fluids and dirt and cause erratic voltages and currents to be applied to the car’s electrical system that can destroy an ECM. They may still charge the battery just fine, but have other internal problems that can damage the sensitive electronics in your car. Bad or loose grounds can allow transient AC voltages and spurious DC currents to enter an ECM and destroy it. Shorted sensors, open wires, and other faults in the wiring can also damage ECMs. The ECM relies on a ground bond between the body and engine block. If there is high resistance here from dirt/corrosion/contamination, even though it will show good on a continuity check, it will cause irregularities in the computer due to higher currents caused by the resistance. A voltage drop test should be used to check grounds rather than continuity tests. Water entry and corrosion of the ECM is also a possibility. If your ECM is actually faulty, you must, absolutely MUST, determine the cause of the failure or else the new one may not last very long.
A primer on testing the ECM, with the caution beforehand that there is much more to an ECM that what I am about to post. An ECM is basically just a set of voltage/current switches and logic ports controlled by a CPU. These work on three things: voltages, currents, and pulses. They can, and should, be tested to confirm replacement is necessary. Most manufacturers even put test ports on the circuit boards for this purpose (they look like little solder blobs labeled like TP1, TP34, etc). The easiest way to test the ECM is to open it up and look/smell for burned, melted, or scorched components. If you see any of that, then for sure it’s bad, no further testing necessary. However, the cause must be found or the new one will meet the same demise. Ok, so no burned parts, no visible damage. This is where it can get complicated, but all you need is a multimeter (preferably a scope, but a meter will work for the basics). Test the circuit board for 12v, 5v, and grounds in the correct places (wiring diagrams will help here…sensor reference voltages are usually 5v, switches and relays get 12v, grounds as noted on the wiring diagram). If you have access to the schematic diagram of the ECM (rare to have this), you can look for the 2.5v-3.3v for the CPU. The other ports, those that are not ground, 12v, and 5v signal, go to open collector transistor circuits, and should be 0v if logic low, 5v if logic high. Logic circuits are harder to test, and should be done with the ECM installed, and key on engine off. An oscilloscope is better for these, as most are pulsed, and operate faster than a meter can refresh. The pulse waveforms show on a meter as randomly moving voltages between 0 and 5v, but are easily seen as a square wave on the scope. How does this help? Incorrect/missing voltages (such as 0v where 12v is supposed to be, 1.6v where 5v is supposed to be, any voltage on a ground, etc) shows what part of the ECM is bad, and can direct you to the cause of what made it go bad. In the case of incorrect voltages, that is almost always caused by ECM voltage regulator damage due to corrosion, bad grounds, or faulty alternator. Just wanted to pass this info on. Maybe it will help, maybe not, but I hope so.
Thank you for this information! It is very informative, and may be able to help me solve my issue. I am not very mechanically inclined, so this stuff is very overwhelming. My car is at the mechanics, and it has been for a week now. He has tried swapping parts, and now is finally starting to test everything. He said that swapping the ECU only worked for a very short time period, so I hope it did not fry the new computer. He says he checked all the wires. He thinks it might be a relay, which he is going to try to switch from another Honda. I am not being charged much. (I’m a broke college student)
Could two relays that the CMP goes into have anything to do with this p1361 code/limp mode?Based on the diagnostic trouble codes (DTCs) you provided, the problem seems to be related to the electrical system and sensors in your car, specifically the Electric Load Detector (ELD) circuit and the TDC sensor circuit. The ELD circuit is responsible for detecting the electrical load on the alternator, while the TDC sensor measures the position of the number 1 piston in relation to top dead center.
It’s possible that replacing the ELD and camshaft position sensor will resolve the issue, but it’s hard to say for sure without further diagnosis. hire the professional .The fact that the car is having trouble staying on and barely driving could indicate a more serious issue, such as a problem with the engine control unit (ECU), fuel system, or other sensors.
Regarding the part number for the ECU, it’s important to find an exact match for your specific make, model, and year of car. The bottom number you mentioned may be a manufacturing code or batch number, but it’s not the part number. You may want to consult with a Honda dealership or a trusted mechanic who specializes in Honda vehicles to ensure you get the correct replacement part.
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