Technical Multiple errors

[Dozzzz]

My 2021 model give all of these Traffic Sign Assist unavailable service required, attention assist unavailable service required, engine light on, no gear information, outside temperature show - -c

Sometimes all go away. Battery is new one.

Fault code p0073

They said that passenger mirror have to change (expensive) , because temperature outside sensor fault for code give? I know that sensor is there at the bottom.

Is it? Should this give all those errors.

 

[Mike1alike]

P0073 means the ECU is seeing an open circuit on the outside temperature sensor, which is why you’re getting “--°C”.
On these Tipos that sensor is usually in the passenger mirror, so that part is correct — but it doesn’t automatically mean the mirror needs replacing.
The fact the fault comes and goes strongly suggests a wiring or connector issue (very common where the loom passes into the mirror/door), rather than the sensor itself.
Also, it’s normal for multiple systems (traffic sign assist, attention assist, etc.) to disable when that signal is missing, as they all rely on shared data.
You should start with cleaning those plugs connectors with contact spray.

 

[Mike1alike]

Simple test: Sensor vs Wiring
Step 1. Access the sensor connector
Under the passenger mirror (or wherever the temp sensor is). Unplug the sensor.
Step 2. Turn ignition ON (MAR). Look at outside temp on dash.
You’ll usually see “-- °C” or very low value (e.g. -40°C).
This = open circuit (expected).
Step 3. Bridge the connector (this is the key)
Use paperclip / small wire.
Connect the two pins on the wiring side (NOT the sensor).
Step 4. Check the dash again
If temperature suddenly shows something “normal” (e.g. 15–30°C) means wiring + ECU are OK and sensor is faulty.
If it still shows “-- °C” or no change means problem is wiring, connector or further up the loom.

The sensor is just a thermistor (resistor).
Bridging the pins = simulates a valid signal.
This is why this test works.

 

[Dozzzz]

Simple test: Sensor vs Wiring
Step 1. Access the sensor connector
Under the passenger mirror (or wherever the temp sensor is). Unplug the sensor.
Step 2. Turn ignition ON (MAR). Look at outside temp on dash.
You’ll usually see “-- °C” or very low value (e.g. -40°C).
This = open circuit (expected).
Step 3. Bridge the connector (this is the key)
Use paperclip / small wire.
Connect the two pins on the wiring side (NOT the sensor).
Step 4. Check the dash again
If temperature suddenly shows something “normal” (e.g. 15–30°C) means wiring + ECU are OK and sensor is faulty.
If it still shows “-- °C” or no change means problem is wiring, connector or further up the loom.

The sensor is just a thermistor (resistor).
Bridging the pins = simulates a valid signal.
This is why this test works.

Yesterday it was Ok and show correct.

In tester before it says +87C.

Ussually it goes mad when it wet weather

 

[Mike1alike]

Ussually it goes mad when it wet weather

That suggests improper connection, oxidised contacts. Do clean the contacts on the circuit.

 

[Dozzzz]

I opened the black cover inside the door. Connector was Ok. I push it little and click.

Is this circuit or something else inside mirror outside. There is only wires going to inside connector?

 

[Mike1alike]

Is this circuit or something else inside mirror outside.

That plus something else inside mirrors.
Use contact spray on those plugs connectors.

 

[Dozzzz]

Okey, thanks. Sorry I am not very pro with these kind of things

 

[Mike1alike]

Also, check and clean the BCM ground feed point. I mentioned the one on my Punto here, you should have something similar.

BCM (Body Computer Module) ground and other electrical gremlins | FIAT Punto (Mk2/2b)

I just discovered the BCM grounding point on my Punto. The electrical system is very similar across most of the FIAT models, so this topic is not Punto exclusive. What happened I noticed idle dipping very short while engine was on warming up temp (40~70 ⁰C) and being stop at red lights. Dipping...

www.fiatforum.com

And of course, cleaning the main ground cable contacts and mating surfaces, the one that goes from battery (-) terminal to chassis and further to gearbox and making sure cable itself is in good condition (no broken wires inside) is very recommended.