SM4 fast flashing error light?

[RAC]

Just wanting to here from anyone here who has seen this intermittently with an sm4.
The guestion is can this this be caused by wiring faults external to the ecu? Its done this a few times, it's normaly only when the ignition is turned on the light will start flashing and you can't talk to it with the laptop. If you unplug the ecu then plug it back in it will be ok for some time. The other day it happend when the owner was driving the car and it cut out, we couldn't get it going at all by unpluging and repluging so he sent it back to the dealer but when he tested it it was working fine and said it must be in the vehicle wiring, the vehicle is still using its stock loom.
When its faulting all the power supplies and earths are correct.

Is there any input/output wiring problems that can make the ecu do this apart from power supplies? When its working fine everything in the software looks perfect.

Just helping a mate out here.

Thanks.

[MRMRacing]

Fast flashing error light on newer Sm4 are mostly a bad connection for the chip. It seems like there are some thing from manufactury on the chipholder. Remove the chip (carfully) clean the legs with electronic cleaner and/or wipe it of with paper. You can see the paper turn dark. Put in the chip in correct location and test. This will solve most problems.:D

[RAC]

Thanks I'll give it a shot.

[RAC]

Just to reply that this worked a treat. Its been working fine since.

Just one more little thing.
This is one of Rays plugin skyline ecus. When the ingition is first turned on there are heaps of magical crank pulses on the crank input and the tacho goes nuts as do the injectors as the ecu thinks the enging is doing 7-9000rpm but the funny thing is you have to have the ignition off for about 3-4min befor it will do the fault again. If you unplug the nissan cas there are no pulses seen on the crack input to the ecu. Another cas has been tried but no luck.
This is flooding the engine befor startup unless he unplugs the cas for the duation of the fuelpump prime then plugs it back in.

Thanks.

[MRMRacing]

This is hard to tell, I have discussed this board with Richard. He thinks this contruction is not good regarding interferance. Have you the diods monuted for stock nissan CAS or do you have changed the trigger disc? I have one with diods and from what I know this car has not this problem.

Else I would start to check the cylinder pulses and cylinder sync wires from the base Sm4 board, an alternative is routing the wires (use shielded) direct from SM4 board to the Nissan connector. Do not let them be routed in the main board with the Nissan connector.

Take special action how the -Ve vires are connected (for hall they should not be used), they are sensitive to pick up noice when not used.
You could try to ground them before doing any other changes.


I have ordered part for making Patch-Looms to Skyline & SM4, just because this problems and it is easier to use a SM4 in other apps also. The SM4 is designed to be inside its alu housing for interferance protection.

[RAC]

Thanks for that. Its using a differant trigger disk. It has a 1.07-4 so doesn't surport the stock nissan trigger and that is what the diodes are for.

With that info i'll do some sorting.

[MRMRacing]

Normally you should not ground the -Ve, make sure first that they are not connected from the Base Sm4 board.

[RAC]

Ok, Thanks.

[MRMRacing]

This is only a temporaly fix, problem will occure again. So for a permanent fix it should be done by the local Autronic dealer. It can fail again and you may be in a situation with the car that is not so good....

Autronic is sorry for the problems it has caused, it was a part that has changed from supplier without notice. They have now worked out a fix that will solve the problem permanently. It should be done at the local dealer to make sure it is done properly, and they have the other parts needed. This is not only cleaning the chip.

It is strongly advised not to fix this by customer themselves, it is easy to crack the socket or miss the other parts needed to fix it permanently.


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