496 ho electrical issue?
03-19-2017 | 07:35 PM
#31
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word of the warning for the unknown Taking the good PCM and putting it on the bad engine can be one way to knock out that good PCM = it very wise to start with the bad PCM and put it on the good running engine and see how its runs.
Then see if it is matching all the engine running parameters in the scan compared when it running with the known good PCM. You have to scan both times before the PCM swap and after with the unknown possible bad PCM. .
Thank whomever I have never knocked out any PCM's because I would not risk the testing of the known good PCM that way but always took the unknown PCM and put it on a known 100 good running engine. I say this because I know boat owners and even so called good techs doing this and ended up knocking out a good ECM / PCM.
The 600 SCI with a bad coil(s) is a prime example of this -Swap and plug a good known PCM in and power up - crank over engine - bad PCM that was good 2 mins ago.
Most likely I could test this PCM as well. My experience has grown a lot in the past 2 years for ECM / PCM testing and some even repaired.
So what fault codes and any spec parameters out of spec ranges on the scan with swapping the good PCM over to bad engine, now runs good ? also you are testing unloaded and below 2500 rpms as well that might not give you the total picture --- but it could as well. Just saying.
Then see if it is matching all the engine running parameters in the scan compared when it running with the known good PCM. You have to scan both times before the PCM swap and after with the unknown possible bad PCM. .
Thank whomever I have never knocked out any PCM's because I would not risk the testing of the known good PCM that way but always took the unknown PCM and put it on a known 100 good running engine. I say this because I know boat owners and even so called good techs doing this and ended up knocking out a good ECM / PCM.
The 600 SCI with a bad coil(s) is a prime example of this -Swap and plug a good known PCM in and power up - crank over engine - bad PCM that was good 2 mins ago.
Most likely I could test this PCM as well. My experience has grown a lot in the past 2 years for ECM / PCM testing and some even repaired.
So what fault codes and any spec parameters out of spec ranges on the scan with swapping the good PCM over to bad engine, now runs good ? also you are testing unloaded and below 2500 rpms as well that might not give you the total picture --- but it could as well. Just saying.
When bad pcm is on "good" motor it stays running but has 2 KNK Sensor codes. And 2 beep alarm every minute. I didn't notice any parameters out of line however I don't do this every day so I could have missed something.
I would say that when I melted the IAC it must have screwed something up in the pcm...?
03-19-2017 | 08:04 PM
#32
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From: Ft. Worth TX
Yes the IAC driver but you could test for that on the scan and with the scan tool. . I hear you also so good luck with it. Just posting to pass along for people to watch out testing systems on marine apps.
03-20-2017 | 01:16 AM
#33
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What ECM MEFI 1 ?
You just do not open up ECM's like with what with a jack knife ?? If he did fix a PCM 555 controller he got darn lucky as hell period.
Also I have been getting into more and more of the ECM and PCM testing if there is a problem with them plus have fixed some as well.
You just do not open up ECM's like with what with a jack knife ?? If he did fix a PCM 555 controller he got darn lucky as hell period.
Also I have been getting into more and more of the ECM and PCM testing if there is a problem with them plus have fixed some as well.
Here's some detailed info on the 1075 HP engine model if interested, http://brucebullockmarine.com/mercur..._1075_sci.html
If so on opening up the PCM 03 model, and knowing Whipple opens up the 555 and 1075SCI almost daily sure makes one wondering the best way to open and close a 555 in order to have a look around? Are you that adventurous Bup?
https://whipplesuperchargers.com/ind...&product_id=73
03-20-2017 | 02:45 AM
#34
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From: Ft. Worth TX
Since sutphen 30 mentioned Merc 1075 HP , it seems he may have opened up Mercruiser's? newer designed (PCM) 03 microprocessor (Propulsion Control Module (PCM) 03 microprocessor: Ignition System: PCM 03 Distributorless) which resembles the looks of item number 3? in the following link, http://www.mercruiserparts.com/bam/s.../31278/14371/5
Here's some detailed info on the 1075 HP engine model if interested, http://brucebullockmarine.com/mercur..._1075_sci.html
If so on opening up the PCM 03 model, and knowing Whipple opens up the 555 and 1075SCI almost daily sure makes one wondering the best way to open and close a 555 in order to have a look around? Are you that adventurous Bup?
https://whipplesuperchargers.com/ind...&product_id=73
Here's some detailed info on the 1075 HP engine model if interested, http://brucebullockmarine.com/mercur..._1075_sci.html
If so on opening up the PCM 03 model, and knowing Whipple opens up the 555 and 1075SCI almost daily sure makes one wondering the best way to open and close a 555 in order to have a look around? Are you that adventurous Bup?
https://whipplesuperchargers.com/ind...&product_id=73
Of course PCM 03 is basically Merc words for a special PCM -- these all came out for the Merc racing engines in 2003 - it still is Motorola 555 -- aka triple nickle -- aka PCM 555 --- no matter how you slice and dice it. And even in some brochures is listed PCM 555 for the Merc racing engines
also in 2007 it was change to PCM 07 as the new calibration for Merc racing engines and so forth but guess what it still was Motorolla 555./ pcm 555 .
http://www.baymarine.com.au/mercury-...i-sterndrives/
PCM 07 can be verify in the link reading above . More of marketing words as the racing division has always separated itself from the black production side.
Just adding --- for my comment on the mefi 1 and jack knife, I was being a smart azz but again its still a 555 (1075 SCi) and I knew that already. Not a hocus pocus - its opened and now sealed shut tight . .
If you like to put a bad pcm /or ecm in my hands to test and possible fix it, but I will state, 1,again not all are fixable and 2, is, I am still working at it so that I become better addressing the possible fixes. . I will not do it for free especially when another services will be billing as well. I will be happy to at least test it if you like ? Saying this in a good way.
I also own a personal 496 so I am very on top of the PCM 555 issues plus whats going on anything that a scan reports . Thanks, if that post was an offer
Last edited by BUP; 03-20-2017 at 03:11 AM.
03-20-2017 | 03:26 AM
#35
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Thanks Bup for the additional info covering the later designed ECM/PCM's numbers. I also recall them having an ECM-09.
Unfortunately I don't have any 555 ECM's laying around and I stopped working on boats professionally at the end of 08 so I'm outdated as far as Merc goes and I don't have access to things/ECM's like that any longer. The post above was just peaking an interest of what it would take to repair one was all....Just thinking out loud of course but maybe someday a member here on OSO would be willing to send you an old/bad one for you to play around with and if so maybe do some sort of technical write up of what you found or possibly repaired mainly since you mentioned you're starting to put some more interest into their failure rate. Fixing forum members ECM's might be a good/easy/fun retirement project someday... $$$.
Unfortunately I don't have any 555 ECM's laying around and I stopped working on boats professionally at the end of 08 so I'm outdated as far as Merc goes and I don't have access to things/ECM's like that any longer. The post above was just peaking an interest of what it would take to repair one was all....Just thinking out loud of course but maybe someday a member here on OSO would be willing to send you an old/bad one for you to play around with and if so maybe do some sort of technical write up of what you found or possibly repaired mainly since you mentioned you're starting to put some more interest into their failure rate. Fixing forum members ECM's might be a good/easy/fun retirement project someday... $$$.
03-20-2017 | 10:24 PM
#37
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From: Ft. Worth TX
to complete the post above as I cut it short ---- PCM 09 which is a Visteon component PCM
PCM / ECM 555 Motorola are no longer being used for years. -
PCM 09 Visteon started in mid to late 2009 for model year 2010. It change again with calibration and name changed to PCM 013 still Visteon component.
At one time Visteon was a Ford owned company. I do not know who currently owns Visteon.
PCM / ECM 555 Motorola are no longer being used for years. -
PCM 09 Visteon started in mid to late 2009 for model year 2010. It change again with calibration and name changed to PCM 013 still Visteon component.
At one time Visteon was a Ford owned company. I do not know who currently owns Visteon.
Last edited by BUP; 03-20-2017 at 10:26 PM.
04-04-2017 | 05:27 PM
#38
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soonenough, Any word from Whipple regarding your PCM yet?
Was following another 496 PCM issue on another forum around the same time as yours and the repair from Whipple turned out to be a failed 4Mhz clock chip inside the PCM, http://www.riverdavesplace.com/forum...=1#post2642245
Below is the main quotes from the other thread,
Was following another 496 PCM issue on another forum around the same time as yours and the repair from Whipple turned out to be a failed 4Mhz clock chip inside the PCM, http://www.riverdavesplace.com/forum...=1#post2642245
Below is the main quotes from the other thread,
496 alarm
Having a problem diagnosing a start/running issue with our Gen2 496.
The engine was running fine when it suddenly shut off. No alarm sounded, just shut off as if I'd turned off the ignition switch.
Currently the engine will still turn over but not start. If I turn the ignition to the ON position nothing happens for 20 seconds. At twenty seconds the fuel pumps start and a solid alarm goes off.
I replaced the fuel pump relay and low pressure fuel pump, but still having the same no start issue.
Having a problem diagnosing a start/running issue with our Gen2 496.
The engine was running fine when it suddenly shut off. No alarm sounded, just shut off as if I'd turned off the ignition switch.
Currently the engine will still turn over but not start. If I turn the ignition to the ON position nothing happens for 20 seconds. At twenty seconds the fuel pumps start and a solid alarm goes off.
I replaced the fuel pump relay and low pressure fuel pump, but still having the same no start issue.
An update. Whipple called today and told me the 4Mhz clock chip in the ECM was toast. Its repaired and on its way back to me. They could not find any indicators or codes to identify if an engine issue caused the ECM damage. They said a few ECMs have come in with the same issue and they appear to have simply failed.
I asked if the IAC could have been the culprit, but it does not appear to be.
I asked if the IAC could have been the culprit, but it does not appear to be.
04-05-2017 | 07:52 PM
#40
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From: Ft. Worth TX
the failed clock chip = the ECM is dead. When you scan the ECM / PCM as far as I have seen is nothing = no communication period from the scan trying to read the ECM / PCM
IMO the chip might have changed from the manufacturers as being part of the problem - prob cheaper quality possible here. Also IMO heat related issue might be the possible cause for the clock chip failure.
If I could ever get of enough ECM failures to look at -- IMO possible I could track down the problem.
Also the OP here I believe can scan his engine ???? plus the engine starts and runs ???? is all of this correct ?? if a scan can be done IMO possible not a clock chip failure.
IMO the chip might have changed from the manufacturers as being part of the problem - prob cheaper quality possible here. Also IMO heat related issue might be the possible cause for the clock chip failure.
If I could ever get of enough ECM failures to look at -- IMO possible I could track down the problem.
Also the OP here I believe can scan his engine ???? plus the engine starts and runs ???? is all of this correct ?? if a scan can be done IMO possible not a clock chip failure.
