How to Bypass the temp sensor - U-Line ?chelon 2175RB-00

code p 0030 refers to heated oxygen sensor (HO2S) 1 bank 1 -heater control-circuit malfunction
code p 0039 refers to turbo/super charger bypass valve , control circuit --range /performance problem===causes --wiring--- bypass valve
code p 74 refers to outside air temperature sensor--circuit intermittent===causes ---wiring---poor connection---out side air temp sensor---ECM
code p 0098 refers to intake air temp (IAT) sensor 2 --circuit high input===causes --wiring short to positive ---IAT sensor---ECM

if you replaced the temp sensor and it still does that check to see if you didnt short the wires if all ok sounds like pcb board

Bad temp sensor

If you bypass the temp sensor for the computer and the fan does not come on, and you know the fan and the relay works, that leaves the computer. The computer grounds the fan relay with a signal from the temp sensor.

Hi there,

The temperature gauge relies on readings from the Engine Coolant Temp (ECT) Sensor.

The ECT sensor is usually located on (or near) the thermostat/coolant housing.

Refer to component No. 8 (2.0L Engine):




Refer to component No. 9 (2.5L Engine) locate under bypass tube:



Hope this helps.


Cheers,

ON your car the temp sensor is located in the bypass tube.

Wow these are hard to find!!

Diagnostic codes for 1987 Pontiac

13 Open Oxygen Sensor Circuit
14 Coolant Temperature Sensor (High Temp Indicated)
15 Coolant Temperature Sensor (Low Temp Indicated)
21 Throttle Position Sensor (Signal Voltage High)
22 Throttle Position Sensor (Signal Voltage Low)
23 Manifold Air Temperature (MAT) Low Temp Indicated
24 Vehicle Speed Sensor (VSS) Circuit
25 Manifold Air Temperature (MAT) High Temp Indicated
32 Exhaust Gas Recirculation (EGR) Vacuum Control
33 Mass Air Flow Sensor (MAF) (GM/SEC High)
34 Mass Air Flow Sensor (MAF) (GM/SEC Low)
41 Cam Sensor Circuit
42 C3-I EST or Bypass Circuit Failure
43 Electronic Spark Control (ESC) Circuit
44 Oxygen Sensor Circuit (Lean Exhaust Indicated)
45 Oxygen Sensor Circuit (Rich Exhaust Indicated)
51 PROM Error
52 CALPAK Error
55 ECM Error
If you have your owners manual they should be in there. I couldn't find one online but did find this.

Future reference
http://autorepair.about.com/library/ts/obd-i/bl-dtcs-28.htm?once=true&

I hope these helped you

Trouble Code 33 and 34 are the MAF/MAP Sensor Circuit. It sounds like you've replaced that sensor already. Did you also have the code 34 before putting in the new sensor?
Or did this code start after it's replacement? Any other codes appearing?

Troubleshooting it would depend if it has the Speed Density Update. The dealer should be able to provide that info.

Here's your fault code list:

13 oxygen sensor circuit 14 coolant temp sensor circuit (high temp) 15 coolant temp sensor circuit (low temp) 21 throttle position sensor (TPS) circuit (high signal) 22 throttle position sensor (TPS) circuit (low signal) 23 manifold air temp (MAT) circuit (low temp) 24 vehicle speed sensor (VSS) circuit 25 manifold air temp (MAT) circuit (high signal) 31 wastegate solenoid electrical circuit 32 exhaust gas recirculation (EGR) circuit 33 mass air flow (MAF) circuit (gm/sec high) 34 mass air flow (MAF) circuit (gm/sec low) 41 cam sensor circuit 42 C3I EST or bypass circuit failure 43 electronic spark control (ESC) circuit 44 oxygen sensor circuit (lean exhaust) 45 oxygen sensor circuit (rich exhaust) 51 PROM error 52 calpak error 55 ECM error