In the wiring harness for an S5 TII, I have a BR/W wire and a BR/B wire (ground) going to multiple sensors (TPS, Pressure Sensor, OMP position sensor, ETC) My question is this. When I plug the pressure sensor in, the Br/b and Br/W wires show that they are "connected" in other words they are showing resistance across them. This is with the harness unplugged from the ECU and all other sensors. Is this normal? Does this mean the pressure sensor is bad? I am getting an error code for the pressure sensor and the OMP position sensor.

Wouldn't this ground out the sensors and throw a code?

 

They should show continuity. Normal as can be.

I think your going about this a bit wrong. You should backprobe the ECU wires with the plugs connected up to the ECU and comparing YOUR readings with those in the FSM section called FUEL AND EMISSIONS, sub section CONTROL UNIT.

 

Thanks Hailers. Well I think I found the problem. The G/B wire to the OMP position pump was broken inside the casing right at the ECU. I backprobed the Br/B and Br/W wire back to the ecu but forgot the G/B wire back. You could not even see that the wire was separated inside the casing. Go figure.

Thanks for the help. I am still getting codes from all of the sensors that I removed from the car during emmisions removal like the stuff on the rats nest. Will this effect the computer/performance of the car since the computer is looking for these and they are not there?

 

Hailers, I don't understand about the br/b and br/w wires showing continuity across them. One is power and one is ground. With every sensor disconnected, they show no continuity. When I plug the sensors in, it "grounds out. I am still getting the code 20 with a different omp position sensor on it. Could it be the ecu? This is the third ECU in this car. It is getting expensive to replace these things.

 

Hailers, I don't understand about the br/b and br/w wires showing continuity across them. One is power and one is ground. With every sensor disconnected, they show no continuity. When I plug the sensors in, it "grounds out. I am still getting the code 20 with a different omp position sensor on it. Could it be the ecu? This is the third ECU in this car. It is getting expensive to replace these things.