Reverse lights problem

[John_Smith]

The scenario is like this:1. Put gear in reverse (manual). No lights + no reverse sensor beep comes out (reverse sensor is tapped from the reverse light wire).2. Checked fuse, gear box reverse switch, voltage (13V).. all are healthy.3. When the wiring harness from the light is plugged out, the reverse sensor works. When plugged in, it doesn't.4. Use a relay, tap in reverse light wire, to act as on/off switch, then tap the power of relay direct to battery, it works fine. Both reverse light + reverse sensor works!But I didn't go for the last modification. I want to trace the root cause of this problem. It seems like there's insufficient power ON both reverse light + reverse sensor. Both were working fine for few years already.Can anyone help?? Thanks!

 

[venger]

Asked Lai already?

 

[jarance]

The scenario is like this:

1. Put gear in reverse (manual). No lights + no reverse sensor beep comes out (reverse sensor is tapped from the reverse light wire).

2. Checked fuse, gear box reverse switch, voltage (13V).. all are healthy.

3. When the wiring harness from the light is plugged out, the reverse sensor works. When plugged in, it doesn't.

4. Use a relay, tap in reverse light wire, to act as on/off switch, then tap the power of relay direct to battery, it works fine. Both reverse light + reverse sensor works!

But I didn't go for the last modification. I want to trace the root cause of this problem. It seems like there's insufficient power ON both reverse light + reverse sensor. Both were working fine for few years already.

Can anyone help??



Thanks!

It look like the light and reverse sensor are OK since they worked when they are disconnect from the system. Your problem seems to be the ground wire or negative wire.

Use a multitester (ohms or buzzer function) to check the negative wire at the light assembly (usually brown colour) to the body. if the resistance is high, then the ground wire is broken or have a bad contact.
If the ground is bad, you can wired a extra ground cable to the reverse sensor module.

 

[John_Smith]

Thanks!
Will give it a try!