Disable Amber Cab Lights

JTRACKER · July 15, 2021

I have searched this forum and Googled myself to death and have not found the right words to get any results to suggest which relay or fuse is used disable the amber cab marker lights.

I would like to put a separate relay or simply a switch in series with the fuse to be able to darken all the amber marker (mirrors included if possible).

California says it's illegal to run these cab markers and want to be able to selectively turn them off.

I have not been able to simply identify the relay which controls the markers at dusk, suggesting a relay is in the circuit somewhere and controlled by one of the computers.

If anyone has any information how to do this it would be appreciated.

Thanks,

JT

gemarsh · July 16, 2021

Can't help you out.

Are you saying CA won't allow the factory installed roof markers?

eyaniv · July 16, 2021

Yes - in CA, you can't have amber, red or blue lights on top of the cab. as far as I know, mirrors are ok.

can you change the LED to white instead?

unit · July 16, 2021

I appears that the OP is correct - CA does not allow them. Trucks built for the CA market have the clearance lights deleted. I think the easiest way to switch the lights would be to loosen the headliner, cut the hot wires to the lights just under the roof and install a switch between the severed ends. The switch wire could be long enough to locate the switch in a convenient location on the dash. It's relatively simple to lower one side of the headliner and reach in to the center of the roof.

2020-2500 · July 16, 2021

So, if I live out of state and have the amber lights but find myself driving through CA with them on would it be a problem?

NWStever · July 16, 2021

Only if you are a conservative! It is afterall the "People's Republic of California" !

JTRACKER · July 17, 2021

Thanks guys for the reply, but was looking for a solution to turn them off when necessary but not permanently.

It seems odd that there is little reference in the manuals or schematics referencing a fuse or relay for these things.

The come on at dusk when auto is selected so there must be a relay connected to them, or at least a fuse that can be pulled.

In the schematic "Sierra 2500HD Body Builder" there is a reference to a relay KR53 but I do not see this referenced in any fuse/relay box.

Oh well, I will keep digging until I find it.

newdude · July 17, 2021

If you wanted them off all the time, pull the driver A pillar trim and unplug it. The roof lights are on their own harness.

Here's the schematic:

If you wanted your mirror markers to work correct still and just disable the cab markers, you'd have to control off of pin H3 circuit 709 or down the line of it or those two connector points along circuit 709. Perhaps you could tie in a switch at the A pillar connector area for the roof marker harness?

Edited July 17, 2021 by newdude

Another JR · July 17, 2021

The two fuses for all of the marker lights (i think minus the mirror markers) are labeled on the inside of the cover of the fuse box under the hood. If you only occasionally want to change whether they operate you could just pull those fuses when you want to disable them. It will disable the fender flare markers as well as the roof markers. On mine, the roof markers are powered with the left fender markers on one of the two circuits.

Have you thought about just covering them so you don’t eliminate the other markers?

Finally, as I think somebody asked above, why? If you are an out of state licensed truck they don’t expect you to alter your lights when you enter the state. Your vehicle was legally sold and licensed in another state with those lights, there is no switch to turn those lights off, and states are required to honor the licensing of visiting vehicles. It’s like the no front plate thing. You can’t get ticketed in a two plate state for driving a vehicle licensed in a one plate state.

Edited July 18, 2021 by Another JR

unit · July 18, 2021

Generally, if you're legal in your home state you're legal anywhere in the nation. There are some exceptions mostly related to maximum payloads on commercial trucks. I don't think I'd worry about a truck with clearance lights ever being mistaken for a public safety vehicle.

Another JR · July 18, 2021

Yeah, the whole thing about CA equating DOT required roof marker lights to a light bar is absurd. They obviously take themselves seriously because they apparently prohibit sales of vehicles with marker lights. However, the difference is visually obvious. I will occasionally travel into CA with my roof marker equipped truck and don’t plan to worry about it one bit. They won’t ticket you, and if they did it would be thrown out simply by you sending a letter citing the state to state reciprocity. requirement. In general at least the state police know this and won’t ticket you.

nards444 · July 18, 2021

4 hours ago, Another JR said:

Yeah, the whole thing about CA equating DOT required roof marker lights to a light bar is absurd. They obviously take themselves seriously because they apparently prohibit sales of vehicles with marker lights. However, the difference is visually obvious. I will occasionally travel into CA with my roof marker equipped truck and don’t plan to worry about it one bit. They won’t ticket you, and if they did it would be thrown out simply by you sending a letter citing the state to state reciprocity. requirement. In general at least the state police know this and won’t ticket you.

I live in NY and I think its bad. I just dont know people in CA do it, I really dont.

RugbyRef · July 20, 2021

@JTRACKER - You could most definitely simply replace the lights with white lights (LED). Recon Truck Accessories has them - Recon Cab Lights. I do not know what year your truck is, so you'll have to make the selection accordingly.

Just in case anyone is interested:

CALIFORNIA VEHICLE CODE - VEH

DIVISION 12. EQUIPMENT OF VEHICLES [24000 - 28160]

CHAPTER 5. Other Equipment [27000 - 28160]

ARTICLE 5. Fenders, Ornaments, and Television [27600 - 27607]

27606.

(a) No person shall own or operate a motor vehicle which is equipped with a light bar, or facsimile thereof, to resemble a motor vehicle used by a peace officer or traffic officer while on duty within that jurisdiction for the primary purpose of enforcing Division 10 (commencing with Section 20000) or Division 11 (commencing with Section 21000) pursuant to Section 40800.

(b) For purposes of this section the following definitions apply:

(1) A “light bar” means any light or device affixed to or mounted upon the roof of a vehicle and extending the width of the roof, or a substantial portion thereof, which emits amber, red, or blue, or any combination of those lights.

(2) A “facsimile of a light bar” is any device designed or contrived to resemble a light bar regardless of the degree of light emission or lack thereof. - Not sure if this is a catchall.

(c) This section shall not apply to a vehicle, if all of the following conditions are satisfied:

(1) The vehicle is possessed by a federal, state, or local historical society or museum that is open to the public.

(2) The vehicle is secured from unauthorized operation.

(3) The vehicle is not operated on any public road or highway, unless one of the following applies:

(A) The vehicle is being operated within a temporary street closure for the purposes of celebrations, parades, local special events, and other purposes when the operation is approved by local authorities having jurisdiction over the street closure.

(B) The vehicle is of a model year of at least twenty-five years prior to the year of operation.

Edited July 20, 2021 by RugbyRef

KCJackson1 · July 21, 2021

Based on that definition posted, I don't know of anyone who has mistaken roof marker lights for a police-style light bar. The roof markers do not meet the definition of "extending the width of the roof, or a substantial portion thereof" - they're just 5 small lights. Nor is it a facsimile of a police-style light bar. No one mistakes them as a police-style light bar on a vehicle that requires them. If they're 100% legal on a dually that requires them, how are they illegal on a SRW truck?

nards444 · July 21, 2021

11 minutes ago, KCJackson1 said:

Based on that definition posted, I don't know of anyone who has mistaken roof marker lights for a police-style light bar. The roof markers do not meet the definition of "extending the width of the roof, or a substantial portion thereof" - they're just 5 small lights. Nor is it a facsimile of a police-style light bar. No one mistakes them as a police-style light bar on a vehicle that requires them. If they're 100% legal on a dually that requires them, how are they illegal on a SRW truck?

Yeah I agree. I think people are mistaken what the definition says. There are yellow bars out there, tow truck, plows etc. The cab lights are not a bar and do not take a majority of the roof. I dont think this thinking is true. GM sells a lot of vehicles to CA, and would make sure of this..