Tip & How-To about Chrysler Sebring

Cold Starting Problems? Consider this before expensive dealership bills!

Almost all vehicles nowadays are equipped with an engine coolant temperature sensor. They are in place to tell the vehicle's computer (PCM) what the temperature of the engine is at any time. In a lot of cases, it acts like an electronic carburetor choke.

For instance, when the temperature outside is 32 degrees F and the car has been sitting outside long enough to cool down to that temperature, the temp reflected from the coolant temp sensor SHOULD be telling the computer, "Its 32 degrees here inside the engine so dump extra fuel so it can start!" (Kind of like a closed choke on carbureted engines, only no moving parts except for the fuel injectors."

But what if that's not what the coolant temp sensor is reading? What if it thinks the temperature is 200 degrees F inside that 32 degree engine? In this case, it will report to the computer that the engine is already warmed up and minimal fuel will be required to start the vehicle. Hence, a hard or no-start!

A mis-calibrated (worn out) coolant temperature sensor can also cause a lot of driveability issues as well. For instance, if this had been the opposite scenario...The engine is actually 200 degrees F but the sensor thinks it's 32 degrees, this will cause the engine to run extremely rich, throw a light on the dash, and most likely stall out.

In my opinion, the coolant temperature sensor is arguably one of the most important sensors on your vehicle. If it's checked and/or changed regularly (I would change it about every 50,000 miles or so) this will be one of much forgotten steps in providing good fuel economy and good driveability...Not to mention good cold starts when the weather outside is frightful!

The good news about replacing this handy little guy? Two things. Inexpensive and easy to replace! The coolant temperature sensor can be purchased at most (if not all) auto parts stores (depending on your make and model regarding immediate availability.) For example, on a '98 Chrysler Sebring, Auto Zone has the sensors available for $25.99.

You can usually locate your coolant temperature sensor on or near the thermostat housing. (Again, vehicle make and model will vary in some cases regarding location.) It will usually have 2 wires leading to it. If you see a sensor with only one wire, you've found the coolant sending unit for your coolant gauge.

I hope this tip has helped you and I wish you another year of safe driving and good driveability!

-Jason_MKG :)

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need a coolant temperature sensor wiring diagram for a 2004 pontiac grand prix gtp


Check engine light on ? The coolant temp sensor is a input to the PCM - engine computer ! All wires come from an go to the PCM . What type of problem are you having ? Maybe able to save you some aggravation an time chasing gremlins . Coolant gauge not working ?
Engine Coolant Temperature Gage
The instrument panel cluster (IPC) displays the engine coolant temperature as determined by the powertrain control module (PCM) or the engine control module (ECM). The IPC receives a serial data message from the PCM/ECM indicating the engine coolant temperature. The engine coolant temperature gage defaults to 100°F (38°C) if there is a malfunction in the engine coolant temperature sensor or the IPC detects a loss of serial data communication with the PCM/ECM.

But if you insist ,you can find free wiring diagram's here http://www.bbbind.com/free_tsb.html Enter vehicle info. year , make , model an engine ! Under system click on engine ,then under subsystem click on fuel controls . Click the search button then the blue link. The second an third diagrams both show coolant temp sensors . Both go to the PCM .

Jul 03, 2017 | Pontiac Grand Prix Cars & Trucks

1 Answer

my mph, gas, and temp gauges are not working


That's why you don't let you husband work on your car ! Unless he does it for a living .. For MPH there is a VSS - vehicle speed sensor , for the gas there is a sending unit in the fuel tank, for the temp. gauge there is a temp. sensor located in coolant stream on the engine .You more then likely need to have you instrument cluster repaired . GM had a problem with step motors inside the instrument cluster . A step motor is what controls the individual gauge. The sensors are all inputs to the PCM - powertrain control module (engine computer ) .
Engine Coolant Temperature Gage
The IPC displays the engine coolant temperature as determined by the PCM. The IPC receives a class 2 message from the PCM indicating the engine coolant temperature. The engine coolant temperature gage defaults to C or below if:
?€¢
The PCM detects a malfunction in the engine coolant temperature sensor circuit.


?€¢
The IPC detects a loss of class 2 communications with the PCM.

Fuel Gage
The IPC displays the fuel level as determined by the PCM. The IPC receives a class 2 message from the PCM indicating the fuel level percent. The fuel gage defaults to empty if:
?€¢
The PCM detects a malfunction in the fuel level sensor circuit.


?€¢
The IPC detects a loss of class 2 communications with the PCM.

When the fuel level is less than 14% (84ohms), the low fuel indicator illuminates.
Odometer
The IPC contains a season odometer and a trip odometer. Momentarily press the trip select/reset switch in order to toggle between the season odometer and the trip odometer. Press the trip select/reset switch for greater than 1.5 seconds, while the trip odometer is displayed, in order to reset the trip odometer. The IPC displays the vehicle mileage and trip mileage as determined by the IPC. The IPC calculates the mileage based on the vehicle speed information from the PCM. The odometer will display 'error' if an internal IPC memory failure is detected.
PRNDL Display
The IPC displays the selected gear position as determined by the PCM. The IPC receives a class 2 message from the PCM indicating the gear position. The PRNDL display shall flash all gear positions if:
?€¢
The PCM detects a malfunction in the transmission range switch circuit.


?€¢
The IPC detects a loss of class 2 communications with the PCM.

Speedometer
The IPC displays the vehicle speed based on the information from the PCM. The PCM converts the data from the vehicle speed sensor to a 4000 pulses per mile signal. The IPC uses the vehicle speed signal circuit from the PCM in order to calculate the vehicle speed. The speedometer defaults to 0 mph (0 kph) if a malfunction in the vehicle speed sensor circuit exists.
Tachometer
The IPC displays the engine speed as determined by the PCM. The IPC receives a class 2 message from the PCM indicating the engine speed. The tachometer will default to 0 rpm if:
?€¢
The PCM detects a malfunction in the engine speed sensor circuit.


?€¢
The IPC detects a loss of class 2 communications with the PCM.

May 22, 2016 | 2002 Buick Century

2 Answers

How the ECT SENSOR WORKS


The ECT (Engine Coolant Temperature) sensor is a thermal variable resistor (also known as a "thermistor"). The ECT delivers a signal to the THW terminal of the Engine Control Module (ECM) which varies with engine coolant temperature. The ECM uses this signal to control the fuel injection system, the overdrive operation on vehicles equipped with electronically controlled overdrive transmissions, spark timing control, idle speed control, fuel pressure control system (if equipped), heated oxygen sensor system (if equipped) and EGR systen (if equipped)

Jun 03, 2011 | 1997 Toyota RAV4

1 Answer

need to find out what color the vss wire is under hood


you don't have a vehicle speed sensor (VSS). You have a wheel speed sensor that tells the PCM vehcile speed in place of the VSS. What are you tring to do?
------------------------------------------------------------------------------------
The electronic engine controls consist of the following:
  • powertrain control module (PCM) (12A650)
  • throttle position sensor
  • idle air control valve
  • camshaft position sensor
  • crankshaft position sensor
  • mass air flow sensor
  • intake air temperature sensor
  • heated oxygen sensor—front
  • heated oxygen sensor—rear
  • knock sensor
  • cylinder head temperature (CHT) sensor
  • power steering pressure (PSP) switch
  • Wheel speed sensor
The powertrain control module needs the following inputs to calibrate the engine properly:
  • camshaft position
  • engine rpm
  • engine coolant temperature
  • amount of engine detonat

Feb 28, 2009 | 1999 Lincoln Town Car

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