Code 43 - ESC circuit failure?

[cuda6pak]

While driving the GN today I noticed that the SES light came on and it is showing a Code 43 - ESC circuit failure? I did a search on here and didnt really find anything. The car didn't seem to run any different than normal under regular driving conditions.

The only thing I did today was install an SMC alky kit real quick which I've done before. Maybe I might have jarred something loose under the dash while messing with the wires?

Anyone know what the ESC circuit failure means? I'm taking her to the track on Friday so I hope it's nothing too big.

 

[GNguy]

CODE 43

Trouble Code 43 indicates that there may be a malfunction in the Electronic Spark Control (ESC) circuit.

ESC is used to sense spark knock (pinging) and retard the timing to eliminate it. A knock sensor (located at the rear of the engine block) sends signals to an ESC module which then signals the ECM that knocking is being detected. The ECM will retard the timing by as much as 20 degrees in 1 degree increments. A loss of knock sensor signal or loss of ground at the ESC module will cause the signal at the ECM to remain high. The ECM will act as if no knock is present, and may possibly result in engine damage, if there is detonation.

Loss of the ESC signal to the ECM will cause the ECM to constantly retard the timing to its maximum. This results in sluggish performance and a Code 43.


The conditions for setting this code are:

Engine is running
ESC input signal has been low more than 2.23 seconds



Typical causes for this code include:

1) Open or shorted knock sensor
2) Loose knock sensor
3) Excessive mechanical noise within engine
4) Improper or incorrectly installed PROM or CALPACK in the ECM or defective ECM
5) Intermittent open in the EST line to the ignition module

courtesy of Gnttype.org

 

[cuda6pak]

I went outside and checked and I'm getting a lot of knock, 13+, just by revving up and driving around. For some reason I didn't notice that earlier. I tried reading the plug to the ESC module where the black/yellow wire comes to with it unplugged and the ignition on and it was only reading .002V.

Where exactly is the knock sensor at? I tried to look on the drivers side towards the firewall for any sensor and couldn't see anything within any sort of reach. Do I have to get underneath the car to see the sensor?

 

[Boost231]

I went outside and checked and I'm getting a lot of knock, 13+, just by revving up and driving around. For some reason I didn't notice that earlier. I tried reading the plug to the ESC module where the black/yellow wire comes to with it unplugged and the ignition on and it was only reading .002V.

Where exactly is the knock sensor at? I tried to look on the drivers side towards the firewall for any sensor and couldn't see anything within any sort of reach. Do I have to get underneath the car to see the sensor?

nope its on top of the engine. its on the drivers side very very back of the engine. its right next to the bell housing of the tranny. it has one wire going to it. let me see if i can find the post where i posted a picture.

 

[Boost231]

cant post the picture from my work computer but do a search for user name PsYcHo GN and he posted a thread called Knock Sensor Location?

 

[cuda6pak]

Found the knock sensor but I don't have a socket big enough to check to see if it's at 14ft-lbs. I also noticed that it only shows 13.4KR on the scanmaster, but not on the Casper's knock gauge??

So since I'm getting lots of KR just by reving and barely driving, does that mean I'm losing signal from the ESC to the ECM somewhere along the way? What should I check??

Also, I don't have any spare knock senores, ignition, or esc modules to test and try with.

I have noticed that very rarely but occasionally it would all of a sudden start giving me knock while just cruising on the interstate, but then I'd back out of it and it'd quit doing it. What other connections can I try to plug/unplug that are related to this problem?

 

[Boost231]

you hear anything banging around? exhaust,dp, something hitting the sensor?

 

[cuda6pak]

you hear anything banging around? exhaust,dp, something hitting the sensor?

No, nothing anymore than usual with the same combo for about 7K miles. Just a little ticking from I think the rockers, but they've sounded the same forever, not real bad at all.

 

[turbofish38]

I had a code 43 just last week. I was testing junkyard ECMs. I used to run the early version of Caspers knock gauge. I removed it many years ago. It used a Scotchlok on the yellow/black(?) wire to the ECM. I'm thinking half of the strands were cut at that spot. A quick solder job on that wire and everything was back to normal.

 

[cuda6pak]

I had a code 43 just last week. I was testing junkyard ECMs. I used to run the early version of Caspers knock gauge. I removed it many years ago. It used a Scotchlok on the yellow/black(?) wire to the ECM. I'm thinking half of the strands were cut at that spot. A quick solder job on that wire and everything was back to normal.

Hmm, I have a Caspers knock gauge that I bought last year and I installed it with scotchlok as well. I will have to double check and try this, thanks!

 

[cuda6pak]

turbofish38, I did a trial run with just taking off the scotchlok (no wires were cut however) and stripping the yellow/black wire back and just tying them together by hand. Wasn't showing any knock as I revved it! Then I unhooked them while it was running and it went back to doing the same thing it was before.

I'm going to twist them all up and solder in the knock gauge with it today and I will post back the results

 

[cuda6pak]

Well I found out what the problem was. Apparently anytime the Casper's knock gauge is tied into the yellow/black knock sensor wire it gives me that code. I just unhooked it from the ecm wire and now it works, but as soon as a try to tie into that sensor for some reason I get the error code. Strange, I guess my knock gauge screwed up? Maybe sending or taking too much signal from the ECM? I found a part of the power wire from the knock gauge that had been chewed up a bit and looked pretty bad, but I cut it and soldered it back together but was still getting the error whenever I tried to tie back into the ECM knock sensor wire. Anyone else had strange problems with there Casper's knock gauge? I've had it installed and untouched for almost a year until now.

 

["Turbo-T"]

Anyone else had strange problems with there Casper's knock gauge? I've had it installed and untouched for almost a year until now.

Yes, as a matter of fact right now I am having issues with my Caspers gauge not resetting after 5 seconds, plus the standby LED doesn't come on at all unless I disconnect the sensing wire, then one of the knock LED's will come on starting with the 2nd green and gradually moving up to the red each time the sensing wire is removed and reattached. I have to shut off the key to get it to reset.

And my gauge is brand new.

Also if anyone can help, I took a voltage reading of the ESC wire (yellow/black wire) with the engine NOT running and the key switch on....I'm getting a 9 volt signal. Caspers thinks my ESC might be going bad....can anyone confirm?