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Link G1 LPV14 problems.

Dennis Wiese

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Link G1 lpv14 problems.


Second user unit.


Problem1 : high scnc/cyl error count


Experiencing Scnc/Cyl error -  getting anything from 134 – 175 counts over 5- 10 minutes of running at high rpm under medium loads upwards ,seems fine off load running in na mode ie under 100 kpa., experienced  while  re calibrating fuel & spark tables.


All wiring check’s out solid when tested with dvm.


Noticed no user options for dizzy input signal conditioning.


Using break out box with 6 inches of cable for ecu install , the VR ‘s are unshielded for the last 6 inches, not had problems before using other types of ecu in this configuration,  will be installing screen cable just to cover all angles and to scope system for any signs of interference. Vehicle ran faultless before on oem ems.



Problem 2: no wastegate control.


wastegate output only pulses when ecu switch on for a few seconds then nothing. used regulated air supplied  set to test pressure connected to link G1 map sensor, set option to perform wastegate regulation  as per instructions for testing wastegate control in G1 manual†nothing happens no oscillating what so ever in the valve, constant nothing no ground what so ever on the  output wire.


Also noticed regardless of changes made  Wastegate DC  shows 102 %.


What about an output transistor damaged, unit brought secondhand in poor install condition.


Any schematics of  Link G1 LPV14 circuit diagram to check output transistors rather than send unit away from UK to NZ .have some experience working on other brands of ecu ,could  backward engineer output drivers if need be.


Any help greatly received.

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You will need to have engine RPM present for the WG solenoid to function. The DC will show 102% until you are above your waste gate hold value.

On these old G1 units the signal conditioning is all handled by the sub-board there is no filtering adjustable by the end user.

What application have you fitted this unit to?

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Thanks simon for your help todate.

unit fitted is this actual unit =  http://i880.photobucket.com/albums/ac4/GaryST165/Link%20ECU/DSC02965.jpg

 installed in toyota celica st185 RC gt4 3sgte rev 2 engine.

 tried again today, no mater what changes made to configuration wastegate dc  remains at 102% red.as mentioned in my last post tested using remote pressure with engine running, makes no difference whether testing or driving.

another session on ecu still the same level of  Scnc/Cyl errors.  error rate increases once over 4500 rpm and once at 5500-6000 rpm error count is one per second if not more, when at low engine speed  no issues apart from  the 1 scnc error  from crank/start up.

scoped g1,g2 ne today nothing un towards just like any other gt4 . i have never like these dizzy setups.

could it be a problem with the sub board., do you have spares, any chance of a schematic diagram to aid scoping the input circuit, not looked at the board yet but it can't be miles of how denso  did it. if no go on the diagram , what sort of time frame and cost would we be talking about. can't see its worth spending to much on an old g1 for repairs and postage around the world twice.

again thanks for your help simon much appreciated.

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If you are lucky you will have a priority setting available in the configuration you could try this on it other available setting (sync or cyl) not sure if this shows on PC you might need a hand controller.

Other wise we might have to see the dizzy and ECU to get it sorted.


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Hi  Simon.

Okay took another look.

Yes Two options for priority  Cyl / Sync...... its set to Cyl. 

A quick question :

Would this be used to select between the two inputs whether NE or G input  between (sync or cyl) no ill effect from switching from either no change to timing table..?

Just to clarify the toyota dizzy arrangement.

The Ne wheel has 24 teeth, driven from camshaft speed = 12 pulses per one crank rotation.

G1 & G2 have one pickup each with one toothed lobe = 1 pulse alternating per 2 camshaft rotations

The layout for the inputs connected to  G1 ecu.

Trig 1 = G1

Trig 2 = Ne

Sync / Cyl Ratio set to 4:1....

What is the sync/cyl ratio about  ,is that the ratio between the ne wheel and the G pulse for snyc/  for decoding 4 cylinder. .just interested as  very little information is in the manual about this ,  having installed this ecu means one has to support it to some degree regardless of its age.

These Link G1 ecu’s are very different from the G3's when it comes to the trigger setup department and having no arming threshold or trigger filtering is  a tad worrying when problems occur..

Will try switching the sync and cyl and report back.


Thanks again Simon  your support is truly noted.
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The Sync/Cyl ratio is dependent on the triggering and the number of cylinders. In most cases it will be the number of cylinders = sync/cyl ratio in cases where the sync is off the crank the ratio will be 1/2 the number of cylinders.

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Had problems today. noticed the spark map has become populated with  loads of 27's and on the event of uploading replacement pcl file a popup nr the end notified of memory errors and to check configiration parameters for correctness. well words to similar effect.. Have put this down to using vista with usb to rs232 . carried out a reload making manual amendments that match the last known good pcl and switched laptops.


The outcome of changing priority  from Cyl  to  Sync made some improvement to error count at high rpm's it's not fixed  but did reduced the rate of  sync errors.


Going to replace the screened dizzy cable as its 20 yrs old and change the loom suppressor , add a few large capacitors to the 12v supply for the  link and hope for the best.


unless you have any other suggestions its not looking good and probably requires  being sent back.


Thanks again Simon for your input.

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