LX FOCUS 2007 Rear Parking Sensors

Rygor · 23-04-2018, 09:46 PM

Anyone got any tips on troubleshooting the rear parking sensors on a 2007 Focus? When you throw it into reverse, you just get a constant tone like when you are too close to something. The sensors are clean, the connections looked tight to the 4 sensors behind the bumper.
Anyone got any pictures on how to unclip the sensor? Could only see it from looking under the bumper and was trying to avoid having to figure out how to remove the bumper if I could.

marg99 · 24-04-2018, 07:49 AM

the control box for the sensors may have died. Not many of the 2007 models came with parking sensors

**russellw** · 24-04-2018, 12:05 PM

I agree that the PAM has probably failed. Below is a pic of the sensor connection and you want to hope you don't have to remove the bumper cover as it requires drilling and riveting.

Oh, and I thought 2007 was LT?

**russellw** · 24-04-2018, 12:20 PM

OK. A bit more information.

If the ignition lock is turned to the position "II" and reverse gear is engaged then the sensors at the rear of the vehicle are activated. A signal is then sounded to indicate readiness for operation. After activation the system performs a self-test. In the event of a fault a signal tone sounds for three seconds at a frequency of 1.5 kHz.

If you are getting more than the 3 seconds then read on ....

The PAM throws a range of DTC's to indicate the actual issue so if you have access to a mobile phone and OBDII software (and a suitable cable) then reading the DTC's is the quickest way to identify cause. Supercheap Auto also offer a code reading service.

The first step is to ensure that the Reverse Lamps illuminate when Ignition is on and reverse is selected. If not then post in this thread for further direction.

There are simple tests that can be conducted with a multimeter if you can access the PAM (mounted on the passenger side rear of the hatch near the floor) then you can undo the connector and perform some basic tests.

Check for Power at the PAM (probably not necessary in this case)

Ignition switch in position II.
Measure the voltage between pin 1 (Green/Yellow wire), harness side and ground.
Should be > 10V.

Check the PAM Grounding
Measure the resistance between the parking aid module pin 16 (Black wire) harness side and ground.
Should be < 5 ohms.
If it isn't then there is a bad ground (usually in the Black/Yellow wire).

Cheers
Russ

Rygor · 24-04-2018, 05:46 PM

Thanks everyone. I don't have an OBD scanner, but was thinking of getting a cheapy one off ebay. I do have a multimeter so will see if I can locate the PAM and check those things mentioned. Reverse lamp does work.

As for the model, I'm going off the Ford servicing records and green slip. This is not the car, but it looks like this:

https://www.carsales.com.au/private/...-4927401/?Cr=6

Bought the car off my sister in law as a temporary second run about. She mentioned the sensors are dodgy. The sensors were working a week or two ago but now it is just a constant on tone.

Rygor · 26-04-2018, 06:33 PM

Would you believe i took the car out yesterday and it started working again... Not sure how long it will stay that way though.

**russellw** · 27-04-2018, 09:25 AM

That probably points to an earthing issue if it is intermittent in nature.

Cheers
Russ

Fast Eddie · 30-04-2018, 01:21 PM

Hi. Russell, I hope you are well! F.Y.I. the LX is the Model one up in Spec from the CL which was the bare-bones model of the MKII (LS, LT, LV Australian designated Model names) Focus. In hindsight it would of been preferable if Ford Aust just designated the Focus MKI, MKII, MKIII and the next-Gen upcoming MKIV. My apologies for going off-topic.