2012 Honda Accord 2.5L 4 cylinder
Had this car apart and check just about everything and all checks out good,
codes on this PCM were as followed,
P062F, P060A, P2610, P1659,
Came to the conclusion the PCM was bad so replaced this for another used one programmed it then the engine started the first time and ran perfectly, let it idle for a few minutes to get to operating temp then revved the engine and it cut out and stalled at 3200rpm then had a hard start, the same thing happened again on the restart, rev to 3200 cuts out and stalls Only code is the P1659 relay replaced did there P1659 Alldate test all checks out,
This car was at the local Honda shop and they sent it out with? now I have headaches 😂
Anyone had anything like this, I'm thinking it's the fuse box,
any help with this will be really appreciated
Good Evening Not sure if you perform idle relean if so, redo Pinpoint test for code P1659 load test all 4pins…
Scope the ignition primary circuits I had one a few months ago with very similar symptoms and codes, it would stall under load, lose communication and crank no start after stalling. It turned out to be a failed ignition coil that was sending over 100 volts to the ECM and shutting it down.
Brandon thanks mate you made me look out of the code box, and went ahead and was checking No.1 coil with a plug in it, I wanted to see if the spark stopped when it reached 3200 rpm and it didn't, it ran perfectly started perfectly on 3 coils, fitted the coil again would stall out and hard start. removed that same coil swapped it over with No.2 and the car runs great now my question is why? LOL…
Secondary ignition energy leaking into the primary circuit and freaking the PCM out. My theory is drive by wire vehicles are very sensitive to throttle control faults so the ECM sees voltage issues and immediately flags a code for ETCS power supply?
I would focus my attention on that 1659 code. Go to the relay and do your testing right there. Do you have 2 powers at the relay on 1 and 4 of the relay? Check the fuse for the relay as well. It looks like #18 of underhood fuse box.
Richard went through all that from start to finish has power on both 1 and 4 good grounds fuse is good. Tried new relay and new main relay 1. Wiring from relay to PCM all check good with both side disconnected, Brandon did you have the 1659 code, Yes, Edward tried the idle relearn, Pinpoint test for code P1659 load test all 4pins…this is my point all checks good, all goes nuts when I get to…
Yes, I had the P1659 as well as some other ECM internal fault codes. It would stall about 50% of the time on a snap throttle.
Branden, yes same here i put in another PCM as said above, the only code I get is the 1659
Check throttle body on live data. Visually inspect throttle plate and inside bore. Clean if necessary and test throttle blade bidirectional test with scan tool. Those years have many throttle body failures. Condition of spark plugs. Oe NGK. amazon and ebay sell counterfeit ngk spark plugs that will cause bunch of gremblins including the dtc you have
Luis, I did the TAC test and it started with .05% to 10% then back to 0.5% then 20% back to .5% then 40% then back to .5% then when it got to 80% it stopped said failed check codes and the code was the 1659. so we know the system is working but whats got me is can a TB cause this 1659
What would Bernie do….. I am thinking 🤔, probably scope ignition injectors, cam and crank etc etc
Do you have any way to monitor the voltage at the relay and the PCM when the cut-out happens? This might help you understand what is happening at the cut-out event.
Matt good idea, let me see what i can try tomorrow.
Hi Gregory it might pay to do voltage drop tests at the ignition switch side have had a few hondas common for electrical ignition switch failures power drop out worth a look in