Honda City: Need help identifying broken wires in engine bay

I noticed that my malfunction indicator light (MIL) on the dashboard was coming on since about 10 days. Today, I opened up the hood to just check after washing my car and found the cut cables.

BHPian SunshineDad recently shared this with other enthusiasts.

In my Honda City ZX 2017, found out this morning that a pair of connecting wires are cut, likely as a result of rats. I would really appreciate and would be of great help if you can look at the attached photos and tell me:

• What wires are those that have been cut? (Circled in red line in photo numbered 1 with arrow showing the connection)
• What is required to fix it? Just the cables or a bigger part?
• Can I have those broken wires patched instead of replacing the whole part?
• How much would be the cost for the parts (and estimated labour, or is it a DIY)?

Further, I noticed that my malfunction indicator light (MIL) on the dashboard was coming on since about 10 days. Today, I opened up the hood to just check after washing my car and found the cut cables. I feel like the MIL and broken wires are related.

Is it logical to first get these broken wires replaced before going for OBD scanning to read the code?

The manual says that the MIL comes on if there is a problem with the Engine Emission Control system, as in screenshot in photo 3. However I have no good idea of all the parts under the hood.

So, I would rather be a better informed owner before I take it to my dealer to get the diagnostic code to begin with.

Thanks in advance for any suggestions and guidance. I cannot afford to spend thousands on this at this time unless it becomes necessary. Magnum Honda in Bangalore says it costs Rs.520 just to run the OBD scanner to pull the code.

Here's what BHPian vigsom had to say on the matter:

Welcome to the "Rodent - MIL Club". I don't think there are many bhpians who have been spared such experiences by rodents.

Now, I'm assuming that except for the MIL on, the car was performing fine, and that is why you noticed this only after 10 days. If yes, then it isn't a serious, but having seen that there is something wrong, best is to get it done.

One question: Is the portion marked white in the following pic part of the wiring harness that has been clipped? How many wires do you see in this cut harness? You might be able to salvage these wires and connect the same wires back to the clipped ends, matching the colours.

It is hard to say from the pic on what those wires exactly are, but the good news is that it can be easily fixed. The MIL has come on because some input to the control unit has lost continuity. I don't know if your car is in warranty, and if it is, Honda will anyways not honour this case since it is a rodent attack. Here is my way forward if you want to go the DIY route.

• Look at a perfect City ZX of same vintage and take a pic of exactly the same harness that has been damaged in your car.
• Look at how many wires run through that harness and see which of those in your car have got damaged.
• If only two are damaged, get two wires preferably of the same colour from an auto electrical store or better still from an auto scrap dealer who has salvaged wiring with them. If you can't get wires of the same colour, you can use any 2 colours but make sure you connect the right colour to the right broken ends. Eg. When you're ready to connect a blue wire you've just got, connect it to both the broken pink ends.
• Disconnect your car battery negative terminal
• Build the continuity of each of the wires that have been clipped by cutting off some insulation at the clipped end, connecting the new wire to both the clipped ends, and taping the connection using insulation tape.
• After the wires are connected, use an electrical corrugated sleeve (the black one with a slit) to protect the wiring.

Once this is all done, connect the battery negative and you should hopefully see the MIL disappear after the ECU learns that all is well. It might take a few minutes of driving before the MIL goes away. If it doesn't go away, get a scan done.

I am attaching a pic of how one wire to a fuel gauge was found cut in my car, and how it was built back using another bit of wire, and finally covered with a sleeve.

Here's what BHPian Mr.Boss had to say on the matter:

MAF sensor harness I believe and it should have 4 wires. You can go ahead and repair it but take proper precautions mentioned in the above post (colour matching, protection sleeves, etc.)

Or if you prefer to change the entire harness, it should cost around 12k for engine room harness.

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