Link CAN Lambda - Errors 16 and 33

[Hyperblade]

Struggling a bit with this one and need some advice.

Initially I was getting the following errors on the CAN Lambda

• 16 heated to long
• 33 open circuit ape-ipe

Searching across the internet, it appears that it can be a broken sensor or noise on the line.

 

I run a Bussmann distribution box with a main 12v feed from alt/battery to a stud which is connected to a common bar which then goes out to relays/fuses.

e.g. Alternator/Battery > Stud > Bar > Relays/Fuses

 

Initially I had one relay feeding the Coils and the CAN Lambda (switched on ignition on).

Version 1:

Alternator/Battery > Stud > Bar > Relay 3 > Coils/CAN Lambda

 

On rereading the suggested setup I changed it to have a dedicated relay just for the CAN Lambda.

Version 2:

Alternator/Battery > Stud > Bar > Relay 10> CAN Lambda

Alternator/Battery > Stud > Bar > Relay 3 > Coils

 

I still got the same errors.

 

However I temporarily connected the 12v for the CAN Lambda to the main stud on the bussmann box bar (where the main feed connects to (so before the bar) and the errors disappeared (did this twice to make sure).

Version 3:

Alternator/Battery > Stud > CAN Lambda

 

The suggested solution for that is the alternative wiring diagram from the Link CAN Lambda Manual where it mentions using a 22uf 35v Electrolytic Capacitor

So I've installed that

Version 4: 

Alternator/Battery > Stud > Bar > Relay 10 > CAN Lambda (Capacitor just before plug)

And this is where it gets weird.

I started the car and had it running and it was still showing error 16 Heated To Long then at the 0:13s mark it started working giving a reading while still showing error 16.

 

Decided that was a bit odd and so stopped the car and started it again with video recording.

I then proceeded to get (in order)

• 42 MES Over Voltage
• 34 Open Circuit RE-IPE
• 16 Heated To Long
• 33 Open Circuit APE-IPE
• Repeating Errors 16/33
• Then at the 1:56 mark it stays on 16 Heated To Long, but again starts working and giving a lambda value.

Here's a video:

 

I'm very confused, it's a brand new loom I have done myself, so there is a high chance of have screwed up somewhere, but I don't know where to start diagnosing this as it's working but not working and I would have thought moving to it's own relay off the common bar would have fixed the issue on it's own.

I would have said the sensor was broken, except it seems to be working...

Engine is a Honda K20a (Euro R) with Link G4X XtremeX in a 84 Toyota Starlet

[Adamw]

Yeah, 16 & 33 are nearly always power supply related.  It can be either wires are too small so there is significant voltage drop, or significant inductive noise.  

If it works fine connected to the main feed then that would suggest it is noise related.  Can you connect to the ECU supply?  That has extra filtering that will clean things up further.  

[Hyperblade]

13 hours ago, Adamw said:

Yeah, 16 & 33 are nearly always power supply related.  It can be either wires are too small so there is significant voltage drop, or significant inductive noise.  

If it works fine connected to the main feed then that would suggest it is noise related.  Can you connect to the ECU supply?  That has extra filtering that will clean things up further.  

I'm running from the bussmann box using 16 AWG Tefzel to a bulk head connector (Deutsch), then 16 AWG Tefzel to the CAN Lambda Unit, with 16 AWG ground to the engine head.

I tried connecting the CAN Lambda to the main stud again to double check everything and I'm getting similar errors

Version 1: Alternator/Battery > Stud > CAN Lambda (Capacitor just before plug)

• 48 APE Over Voltage
• 34 Open Circuit RE-IPE
• 16 Heated To Long
• Repeat 16/33
• Then Lambda works (with error 16 Heated To Long still showing)

 

So I then tried going to the feed to the ECU and got the same errors.

Version 2: Alternator/Battery > Stud > Bar > Relay 1 (to ECU as well) > CAN Lambda (Capacitor just before plug)

• 48 APE Over Voltage
• 34 Open Circuit RE-IPE
• 16 Heated To Long
• Repeat 16/33
• Then Lambda works (with error 16 Heated To Long still showing)

Does the fact that the lambda is working eventually, I assume when it's naturally got up to temp or using less current to get there, suggest a power supply issue (voltage drop?), rather then a CAN Lambda Unit/Sensor issue?

If so what's the best way to verify that?

[Adamw]

Have you got a jumper pack or something you can try powering it from?

[Hyperblade]

8 hours ago, Adamw said:

Have you got a jumper pack or something you can try powering it from?

Thanks for the help.

 

No I don't, So I tried something different.

I figured I would eliminate the bulkhead connector so direct wired the main feed (from the bussmann stud and ground to another location.

That appeared to work, so I changed the ground back to the original location that still worked.

So figuring I had narrowed it down to perhaps the bulkhead connector being the issue I pulled the pin out on the socket side and put a new cable and pin in (left engine loom side).

I then hard wired the new pin to main stud, and it worked.

I figured at this point maybe the cable from the bussmann had something wrong with it. So I wired in a new one (16awg again)

Errors came back.

So then I went straight from bussmann stud to the new pin and I got the same errors (this previously worked fine).

I then shut the car down, started it back up and the errors have gone away again.

 

I've measured the voltage at just before the bulkhead connector at 14.37v consistently through all the chopping and changing.

I am getting a 48 Over Voltage error now as well on startup.

The lambda is actually reading a value through most of this after a delay.

 

I'm left even more confused now, I thought I was narrowing it down, but now I don't think so, it just seems so random.

 

Here's a picture of the setup that both worked, and didn't (back to back 1 min in between) that's 12awg to 16awg at the bulkhead connector.

 

Any thoughts on what to try next?

 

[Hyperblade]

On 10/6/2021 at 12:13 PM, Adamw said:

Have you got a jumper pack or something you can try powering it from?

Ok, I've managed to get it going consistently and also erroring consistently, was tricky with no jumper pack / spare battery.

The issue is actually with the CAN Lambda ground which was wired up to go straight to the cylinder head (along with coils, ecu grounds etc all in same location.)

After a lot of mucking around I've stumbled onto the fact that when it's ground to the chassis it works fine, but if it's grounded to the head it shows the errors, I changed location on the head to a spare bolt, but it caused the same errors.

So I changed the ground from the engine to the chassis end closer to the battery, but still get the errors when the CAN Lambda is ground to the head.

So does that confirm it's a noise issue? (same wire is used when going to chassis vs head)

Is there any common causes, and solutions for that?

 

[Adamw]

33 minutes ago, Hyperblade said:

So does that confirm it's a noise issue? (same wire is used when going to chassis vs head)

Yep I would say that confirms it is likely noise.  

The biggest electrical noise connected to the engine would be the ignition coils if there is a large loop area.  Does you coil power supply have a supressor on it?  Im not sure if the K20s have one factory of not - but if not the factory may have kept the loop short using other methods.  

Im pretty sure the K20 coils only have 3 pins, so the the secondary winding actually "grounds" through the 12V supply pin. If there is no supressor, then for the spark to complete its circuit back to the coil, the spark goes out the end of the coil to the spark plug, jumps the gap to the electrode, through the cylinder head, to the ground cable back to the battery, through the battery, back down the 12V wire, through ign switch etc and eventually back to the coil though the 12V pin.  With a supressor on the coil power supply this effectively creates a short to ground when a high frequency passes through it so the loop is much shorter.  

Have a look at the example at 8:24 in this Adaptronic video:  https://youtu.be/ZTDsm6b69Lk

 

[Hyperblade]

10 hours ago, Adamw said:

Yep I would say that confirms it is likely noise.  

The biggest electrical noise connected to the engine would be the ignition coils if there is a large loop area.  Does you coil power supply have a supressor on it?  Im not sure if the K20s have one factory of not - but if not the factory may have kept the loop short using other methods.  

Im pretty sure the K20 coils only have 3 pins, so the the secondary winding actually "grounds" through the 12V supply pin. If there is no supressor, then for the spark to complete its circuit back to the coil, the spark goes out the end of the coil to the spark plug, jumps the gap to the electrode, through the cylinder head, to the ground cable back to the battery, through the battery, back down the 12V wire, through ign switch etc and eventually back to the coil though the 12V pin.  With a supressor on the coil power supply this effectively creates a short to ground when a high frequency passes through it so the loop is much shorter.  

Have a look at the example at 8:24 in this Adaptronic video:  https://youtu.be/ZTDsm6b69Lk

 

The K20a doesn't run a suppressor.

Thanks all the info and the help, really appreciated.

[Hyperblade]

On 10/8/2021 at 8:25 AM, Hyperblade said:

The K20a doesn't run a suppressor.

Thanks all the info and the help, really appreciated.

Just to follow up on this thread, I've left the CAN Lambda grounded to the chassis and it's all been dyno tuned and everything is reliable.
Not exactly the ideal setup I wanted, but nothing else was affected by the noise.
It would be nice if the Link CAN Lambda unit just handled the noise like everything else, e.g. the link ecu which was also ground to the same place on the head which works fine...