AEL 97 D1 P1196 can't smog.

Icannap1

Well-known member
Mar 3, 2015
123
21
OC, CA
I have a P1196 that will pop up and not complete the catalyst portion of the computer. I have checked both rear o2 sensors and they appear to be working correctly, I swapped them out from right to left and reset the code but I still get a P1196. I have pinned out the complete o2 harness from pin to pin and it all rings out, wiggled the connectors and they ring out perfect continuity. I have 12 volts at the heater portion of the sensor, and I have voltage at the sensor that is variable. From a cold start engine cold the truck is in open loop about a minute later it is in closed loop that seems a little odd as the engine has not reached full operating temperature. There is two temperature sensors on the intake manifold one has a 2 pin connector and the other has a 1 pin connector one is for the gauge the other is for the computer management. Not sure which of the two is for what but shouldn't the computer go from open loop to closed loop once the engine has reached operating temperature, not sure if this is related but the only code I get is a P1196 and the only info I can find is P1196 - Oxygen Sensor Heater Type 2 Low Resistance Downstream. What side is it? Has anyone come across this and what did you do to resolve it?
 

discostew

Well-known member
Sep 14, 2010
7,706
1,015
Northern Illinois
Its kind of hard to get some tests to run. There is a long drawn out drive cycle that should get most of them to test themselves. Sometimes its a vac. leak causing fuel trims to not be right. If you have a scanner look at the readings from the temp sensors your taliking about and make sure the computer knows the actual temp.

The code is for the o2 sensor heaters in the rear sensors. Should be pretty easy. The heater can be measured with a meter, one of them is open or the wires could be damaged or broken.
 

WaltNYC

Well-known member
Mar 3, 2010
707
135
NYC
P1196 doesn't appear to distinguish between one bad sensor or two bad sensors. Could be one, could be both.

How can you determine that "...checked both rear o2 sensors and they appear to be working correctly" ?

The GEMS OBD manual can be found among the docs in the link in my signature. In the D1 section. Feel free to help yourself to any/all.

I suspect a bad O2 sensor. Trouble is determining which one.

It has been suggested, though I don't know for sure, that it is better to replace both at the same time.
 

Icannap1

Well-known member
Mar 3, 2015
123
21
OC, CA
Had a bad O2 sensor causing the P1196 code, replaced the bad sensor and has had no code return. The evap portion of the test has completed but I have not been able to complete the catalyst portion of it. Have tried to perform drive cycle but with no luck. Has anyone had the same luck and what did you do to remedy it?
 

Icannap1

Well-known member
Mar 3, 2015
123
21
OC, CA
Update: Still no codes, the bad 02 sensor was the problem for the P1196 code, I have also tried the drive cycles, and had no luck. I also took it to a indie rover shop they racked it and were unable to complete the drive cycle. They recommended driving it till it completed that portion of the test as racking it has no load on the drive train. Has anyone found a way to complete the drive cycle with a stubborn rover?
 

Icannap1

Well-known member
Mar 3, 2015
123
21
OC, CA
I have the Torque app on a Android device and Car Scanner pro on Windows. What I have noticed are two things: first is when I let up on the gas it will go to "Open Loop and due to insufficient engine temperature", and second I have noticed that the ECM OBD module voltage drops to 10V see attached image. Looking at the Rave I see that P127 F3 20A fuse goes to C1026 pin 4 located behind the windshield washer fluid bottle it then feeds +12v to S145 splices between and feeds the following circuits ECM, Multi Function relay, O2 sensors, and ignition coils. I think there is a current drop at C1026 or somewhere down the line on the WG (White Green) wire and this is probably the culprit. I will check it this week. I need to get this done so I can smog it. If the voltage drop is not at the connector I will need to trace it down. I have 12.6 at the battery while it is running seems a little low when running and everything is on lights, spots, compressor, AC, you name it. Engine off and everything off 12.2 volts at battery and fuse box by battery.
 
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Icannap1

Well-known member
Mar 3, 2015
123
21
OC, CA
I was thinking the same thing.
Get an OBDII dongle and Torque app. It will give you the MIL status so you know when to time it right. ;)

I thought the Catalyst portion had to be completed that is what the smog guy told me. If you look at the first picture there is no mil is off and dtc is 0. what do you mean by time it right? I am still having an issue with voltage output from the alternator when it's cold it has 13.9 volts but as soon as it warms up with the engine it drops down to 11.3 - 10 volts. the odd thing is that it runs fine it just doesn't register when I try to do the drive cycle so the catalyst portion of the test will not complete. I just hope when I replace the alternator that the voltage to the ecm allows the test to complete once the drive cycle has been completed. It would be cool if I could retain the memory on another ecm that had the completed drive cycle then swapped to my rover and take the test to get it over with but as soon as you remove the unit it will loose power so back to where you started at.:banghead:
 

squirt

Well-known member
Nov 13, 2008
824
13
Los Angeles
Can you get it in the sweet spot of no code and just one counter not ready? In CA you can have one counter incomplete and pass smog.

You can have monitoring incomplete on one system, but it CANNOT be catalyst.

OP, how many miles have you driven? I've found that some vehicles need about a week of mixed highway/city driving in order to get passing readiness on that catalyst system. Multiple cold start/shutdowns may also be necessary. Naturally, every time you clear codes, the process will re-start. Have you driven for a week or more without messing with the ECU or disconnecting power?
 

Icannap1

Well-known member
Mar 3, 2015
123
21
OC, CA
I have been driving it but not daily, about 3 times a week, and around 40 miles when I do round trip. Have not been messing with the ECU except to see if it is ready for smog. No codes for a month so no need to clear. This rover is very stubborn but she runs great.