Code 43 info
Thread Starter
Cruising
Joined: Jun 2021
Posts: 14
Likes: 1
Code 43 info
I know this topic has come up a million times but I’m looking for info on code 43. I recently bought a 92 convertible and in the last week the SES has been coming on intermittently. It only stays on for about a minute and the only code in the history is 43. There also doesn’t seem to be any consistency when it comes on either as it’s come on at start up, coasting to a red light, driving in the city, etc.
I’ve read about diagnosing the sensors, wiring, etc. but haven’t had time to do it yet.
I’m wondering if that code gets thrown if a knock is detected or only if there is a fault with the system? Will damage occur if I continue driving while this problem is intermittent?
I’ve read about diagnosing the sensors, wiring, etc. but haven’t had time to do it yet.
I’m wondering if that code gets thrown if a knock is detected or only if there is a fault with the system? Will damage occur if I continue driving while this problem is intermittent?
Drifting
Joined: Apr 2020
Posts: 1,925
Likes: 610
From: Orange, CA
Code 43 on our cars is due to a fragile resistor inside the knock sensor going bad. Very often, the resistor fails even though the knock sensor itself is perfectly fine. Replacing the sensor will resolve the issue, as will disabling the code by replacing the chip in the ECM.
Thread Starter
Cruising
Joined: Jun 2021
Posts: 14
Likes: 1
Code 43 on our cars is due to a fragile resistor inside the knock sensor going bad. Very often, the resistor fails even though the knock sensor itself is perfectly fine. Replacing the sensor will resolve the issue, as will disabling the code by replacing the chip in the ECM.
Drifting
Joined: Apr 2020
Posts: 1,925
Likes: 610
From: Orange, CA
The only C4 to be spared this horrible fate is the 96, which reverted to the previous knock sensor design that didn't have the resistor, because it detects the presence of the knock sensors by...yanno...actually looking at the output of the sensor itself.
All C4s before the 96 cannot actually tell if the sensor is doing its job or not. Code 43 just means, "Hey, where'd that resistance go!?"
Thread Starter
Cruising
Joined: Jun 2021
Posts: 14
Likes: 1
Correct. All it means is that the resistance of the knock sensor is outside the acceptable range. 99% of the time this is because the resistor GM added to the knock sensor for our cars has failed. It is far more fragile than the sensor itself.
The only C4 to be spared this horrible fate is the 96, which reverted to the previous knock sensor design that didn't have the resistor, because it detects the presence of the knock sensors by...yanno...actually looking at the output of the sensor itself.
All C4s before the 96 cannot actually tell if the sensor is doing its job or not. Code 43 just means, "Hey, where'd that resistance go!?"
The only C4 to be spared this horrible fate is the 96, which reverted to the previous knock sensor design that didn't have the resistor, because it detects the presence of the knock sensors by...yanno...actually looking at the output of the sensor itself.
All C4s before the 96 cannot actually tell if the sensor is doing its job or not. Code 43 just means, "Hey, where'd that resistance go!?"
