Knock Sensor Wiring Thread

[travisimo]

Before anyone asks, yes I searched extensively, but I could not find a thread that would tell me the wire colors leading to the female harness plug.

Suddenly, as I was driving the truck I got a P030 code when I went to inspect the front knock sensor was disconnected, and the female harness plug was nowhere to be found.

I did finally locate a long red wire pictured below. More than long enough to be for the knock sensor but you can see it may have been added to by a PO.

Similarly, I went to check the rear sensor and noticed the wire was hanging on by a thread and when I removed the rear sensor the female harness came off but, the wire attached was a blue wire going into the harness.

I’ve ordered the pigtails but I still need any info I can gather about if I’m good with rewiring these wires to the sensors or if I’m off base. Thanks in advance.

 

[Kernal]

Which Model (year) FZJ80 are you working on, 93-94 or 95-97?

 

[travisimo]

95! Sorry I didn’t mention that.

 

[Shipwreck]

If your '95 has the same wire harness as my '97, and I think it does, then the front knock sensor wire should be black and the rear is blue w/ white stripe.

 

[travisimo]

If your '95 has the same wire harness as my '97, and I think it does, then the front knock sensor wire should be black and the rear is blue w/ white stripe.

View attachment 4184135

Excellent thank you very much for verifying. I can not wait to finally have this fixed.

 

[Vaudo]

Excellent thank you very much for verifying. I can not wait to finally have this fixed.

Did you get this fixed? I have newer sensors and get p0330. I ran a new wire to both sensors but apparently I need to redo it because you have to a)used RG58 coaxial cable and b) ground the shielding before the cable enters in through the fire wall. I was hoping to find some video or direction on this.

 

[travisimo]

Did you get this fixed? I have newer sensors and get p0330. I ran a new wire to both sensors but apparently I need to redo it because you have to a)used RG58 coaxial cable and b) ground the shielding before the cable enters in through the fire wall. I was hoping to find some video or direction on this.

I ordered new harness connectors and they haven’t arrived yet. Fed Ex and UPS both have really suffered in recent months. The shipment was 4 days late and then someone stole the box out of my mail box haha! It’s extremely frustrating.

 

[OGBeno]

Or
You can just get a 5VZ-FE knock sensor sub-harness and chop the end off and wire in. Easy peasy. Been doing this factory option for 20 years.

 

[Vaudo]

Or
You can just get a 5VZ-FE knock sensor sub-harness and chop the end off and wire in. Easy peasy. Been doing this factory option for 20 years.

View attachment 4188221

Yeah, that'd be nice but there is likely some damage in that harness. I am now getting a P0125 error which shares that same loom. Thanks for the thought though.

 

[OGBeno]

Yeah, that'd be nice but there is likely some damage in that harness. I am now getting a P0125 error which shares that same loom. Thanks for the thought though.

Cool. Either buy a new OEM harness. 82121-60343

Or fix your wiring.

None of this is rocket science.