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Discussion Starter #1
Can anyone help me with there's codes
P1574 and c1295 i can’t get rid of em

ABS light is on
brake light are working
code's set to current as soon the key is turned on

done so far:
new light bulbs
new stoplight switch (the one on the brake paddle)
tested another ebtcm module

got 12v on pin 9 on the ebtcm harness when pressing down on the brake

its driving me nuts ive a apk (state inspection) due in a few weeks and it’s a fail point over here (here is the netherlands)


if anyone has an idea ide appreciate it very much

Richard
 

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-Administrator- 2002.5 F55 STS 2014 FWD Explorer
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Most often caused by either bad bulb(s), sockets, or wiring in the rear brake lamp/tail lamp circuits. Your wiring runs in a channel in the left trunk hinge arm and there have been problems with broken/chafed wires where the harness leaves the channel and runs into the trunk near the LR wheelwell. There's also a ground connection at the LR wheelwell metal which has caused problems.

Otherwise, the brake light switch over the pedal almost up against the firewall.
 

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Discussion Starter #6
Ok so i still got the problem with
P1574 - Stoplamp Switch Circuit
C1295 - Brake Lamp Switch Circuit Open

Things I tried so far are
- new light bulbs
- new stoplight switch – that’s the one with the 2 plugs right?????????
- tested another ebtcm module
- cleaned the ebtcm connector and module again
- got battery power on pin 9 on the ebtcm plug when i press the brake
- got battery power at the stoplight switch
- brake lights are working including the 3th brakelight
- ran a new ground for the brake light’s


there 2 switches on the brake paddle one is the stoplamp and one is tcc brake switch
according to the service manual (if I read it right) I should check the stop/btsi/cruise brake switch

but I don’t really get why cuz if my tcc light is on should I not check the tcc brake switch?:bonkers:
 

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Discussion Starter #8
woeps i mixed the abs with tc light up in my first post :thepan: sorry about that

my abs light is off so no probs there, its the traction control light that’s on (the light in the left lower corner) and only have those 2 codes set current there are no history code's, if i clear the codes the tc light goes off for a few seconds till the code's return
 

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:hmm: I did not think that a brake lamp switch would affect the T/C. I would more suspect a wheel speed sensor, but you have no such codes.
 

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Discussion Starter #10
nope no code's for the wheel speed sensor
also checked codes wile driving with the tc light on but it only give those 2 code's

if i clear those 2 codes the traction control light goes off till they set again.
so it gotta do with those 2 otherwise it wouldn’t turn off right?
 

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Theres a capacitor wired across the brake switch contacts, maybe that has open circuited. There should be an orange and white wire attached to the switch that is the power and feed to the EBTCM, the brake light, and cruise control circuits there should also be a black wire on each side of the switch, those are the wires to the capacitor.
 

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Discussion Starter #13
I do see the capacitor its directly hooked up onto the plug
any idea how much volt / ohm or whatever it should measure on the orange and white wire or across the capacitor?

thanks for your help
Richard
 

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You need an analog ohm meter, set your needle meter to an OHM scale. With wires off of the capacitor or the car wiring disconnected from the stop switch, and the brake switch open (no pressure on the brake pedal) touch the cap terminals, the needle should move away from the infinity and move slightly towards 0 ohms and then go back to infinity...reverse leads and on the cap and the needle should move away from infinity even further and then go back to infinity = a good cap. If the meter needle goes all the way over to 0 and stays there = a shorted capacitor If the needle doesn't move at all you have an open capacitor. You have to discharge the capacitor between each test as it picks up a charge from the ohmmeter during the test.
 

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Discussion Starter #15
It works :cloud9:
it was the capacitor that was defective, replaced it with a new one and no more TC warning light and no more codes!

thanks for the help Mark!

Richard
 

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It was open circuited wasn't it? Can you actually buy that part from GM, or is it part of the switch?

Good thing it was that, because the next step after checking that and the switch itself was new EBTCM.
 

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Discussion Starter #17
Ya it was a open circuited, i got a new one from a electrical part store, i just unsolder it from the connector, its not part of the switch itself but its on the switch connector

i took it with me to the store, they gave me a new one, did look different but hey it works so who care's, GM as dealer or part house doesn’t exist here anymore, they didn’t survival :(
So its getting real difficult to get parts for GM’s here…
 

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I think the function of that capacitor is to supervise the wiring between the switch and the EBTCM. It leaves voltage on the circuit when the brake switch is open but not enough current to light the brake lights or trip the cruise control module. If it wasn't there and the wire broke the EBTCM would never know. Its not mentioned anywhere in the service manual other than the wiring diagrams and its not in the trouble shooting section for that code. I've often wondered how how the car knows if the brake switch circuit is open, since thats its normal condition, unless the brakes are applie. It misleads you into thinking the switch is bad, instead of the wiring (or in this case the capacitor), its kind of a bad name for that particular DTC.
 

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That was a good call Mark, I will have to put that one away in my fixit file for future reference, I too looked at the diagnostic routine and saw the replacement of the EBTCM as next on his list, I was wondering what the problem was when he mentioned that he tried another one. Thanks for the tip.
 
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