Where would it be?

Dear Mr. B>

Hope you're well. There is no switch to turn-off the "Check Engine Light". That light comes-on because there's a malfunction, that affects pollution-controls, e.g., if the oxygen sensor fails. Repairing the failed item causes the light to go out.

In some cases, it is needful to disconnect the negative battery cable blamp from the battery's negative terminal. Cutting power will require You to use the radio's four-digit security code to return the radio to operation.

If the "Service" light is on, that can be turned-off. On the left side of the speedometer, there's a "button" accessed by removing a small black rubber plug in the instrument cluster's clear plastic faceplate. The plug can be removed by using a small, flat-blade screw-driver. Then, use a ballpoint pen to push on the "button".

Go gently, when replacing the black rubber plug in the instrument cluster's faceplate. If too much force is used and the rubber plug ends-up behind the instrument cluster's faceplage, the cluster must be removed and dismantled to allow the plug to be recovered.

Hope this helps.

Yours faithfully,

Spook

Thank you for your suggestions. However, the CEL was tripped when my son hit a bump and the resonator separated from the exhaust pipe, and when that was repaired, the CEL remained on, which it shouldn't have, thus the inquiry.

Dear Mr. B.,

Hope you're well. Thank you, for the explanation. I'd check for fault codes using the ODB readers, on the front face of the driver's-side strut tower. If no codes show, i.e., if all readouts are 1-1-1, then, I'd try to re-set the Check Engine Light (CEL). To do that, disconnect the negative battery cable clamp from the negative battery terminal, and wait 20 minutes.

Before cutting power to the entire car, be sure you have handy the radio security code. If you do not have the radio security code, call a Volvo dealer's service department and provide the Vehicle Identification Number (VIN). If the radio is a Volvo unit, but not that installed at the factory, you'll have to remove the radio in order to get the radio's serial number. Each radio has a serial number, which I believe a dealer service department can use to get the security code.

If the CEL remains lit after power is restored, I'd inspect the exhaust system for other damage, e.g., a failed oxygen sensor, damaged catalytic converter, etc.

An impact sufficient to separate exhaust system components could have done other damage.

Hope this helps.

Yours faithfully,

Spook

Instead of pulling the battery cable, you can remove fuse #1 for about 30 seconds, with the key off. Light should go out. Won't affect the battery.

You are actually incorrect. On ODB-I systems the CEL stays on until the codes have been cleared. You can do that with the method mentioned or by reading them from the blinking light code reader in the engine bay and then resetting them.

Let us know if you want to read the codes and find out for sure if you have anything else wrong. The procedure is in the FAQ's but we could provide a direct link to the page.