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Ok trying to start from scratch. I did a power & ground test on the plug that goes into the RVC here are the results, Mike where should I go from here?
Terminal 30 refers to battery feeds that are always live. Terminal (or circuit) 15 is power switched by the ignition switch. All four of the fuses that feed the RVC are terminal 30. You show battery voltage at all 4 of these feeds. However, the B1402-1 and B1403-1 codes actually read something like 'Left Rear Window power relay not operating or no terminal 30'. I think the module is monitoring the output voltage to the motors and throws a code if the relay is commanded to turn on power, but not voltages is seen at the output. This could be a bad relay, possibly a bad control circuit, or bad power supply. If you can back probe the plug with it connected, check pins 10 and 12 while you try to operated the windows. If voltage levels stay good, you probably have good supply power. You can also back probe pins 7, 8, 11, and 14 while attempting to lower the rear windows. One pin in each pair should have battery voltage and one should have continuity to ground. This will reverse when commanded window direction changes. Finally, try providing ground and voltage to the 7/8 pair and the 11/14 pair to the plug side (with the plug off). This should move the respective window and reversing the wires should change direction
I'm not sure how you would see voltage at pin 8. Pins 7&8 and 11&14 are just the motor leads from each rear motor. With the plug unplugged from the roof module, there should not be any voltage nor continuity to ground on these leads. Double check that reading. If you really do have voltage there, you need to trace the wires and figure out why.
Terminal 30 refers to battery feeds that are always live. Terminal (or circuit) 15 is power switched by the ignition switch. All four of the fuses that feed the RVC are terminal 30. You show battery voltage at all 4 of these feeds. However, the B1402-1 and B1403-1 codes actually read something like 'Left Rear Window power relay not operating or no terminal 30'. I think the module is monitoring the output voltage to the motors and throws a code if the relay is commanded to turn on power, but not voltages is seen at the output. This could be a bad relay, possibly a bad control circuit, or bad power supply. If you can back probe the plug with it connected, check pins 10 and 12 while you try to operated the windows. If voltage levels stay good, you probably have good supply power. You can also back probe pins 7, 8, 11, and 14 while attempting to lower the rear windows. One pin in each pair should have battery voltage and one should have continuity to ground. This will reverse when commanded window direction changes. Finally, try providing ground and voltage to the 7/8 pair and the 11/14 pair to the plug side (with the plug off). This should move the respective window and reversing the wires should change direction
I'm not sure how you would see voltage at pin 8. Pins 7&8 and 11&14 are just the motor leads from each rear motor. With the plug unplugged from the roof module, there should not be any voltage nor continuity to ground on these leads. Double check that reading. If you really do have voltage there, you need to trace the wires and figure out why.
thanks I will check on my next day off [Wednesday ] & will post results, I need a miracle, I’m also replacing my battery. It’s 6 years old. I know I’m throwing money at this , I also have new SAM’s coming …..
Terminal 30 refers to battery feeds that are always live. Terminal (or circuit) 15 is power switched by the ignition switch. All four of the fuses that feed the RVC are terminal 30. You show battery voltage at all 4 of these feeds. However, the B1402-1 and B1403-1 codes actually read something like 'Left Rear Window power relay not operating or no terminal 30'. I think the module is monitoring the output voltage to the motors and throws a code if the relay is commanded to turn on power, but not voltages is seen at the output. This could be a bad relay, possibly a bad control circuit, or bad power supply. If you can back probe the plug with it connected, check pins 10 and 12 while you try to operated the windows. If voltage levels stay good, you probably have good supply power. You can also back probe pins 7, 8, 11, and 14 while attempting to lower the rear windows. One pin in each pair should have battery voltage and one should have continuity to ground. This will reverse when commanded window direction changes. Finally, try providing ground and voltage to the 7/8 pair and the 11/14 pair to the plug side (with the plug off). This should move the respective window and reversing the wires should change direction
I'm not sure how you would see voltage at pin 8. Pins 7&8 and 11&14 are just the motor leads from each rear motor. With the plug unplugged from the roof module, there should not be any voltage nor continuity to ground on these leads. Double check that reading. If you really do have voltage there, you need to trace the wires and figure out why.
Ok back probing yelled no response while plug was in RVC except voltage levels on 10 & 12 stayed consistent, i was able to operate the windows from the plug with my power probe ( so no short from plug to windows )…. I must have probed wrong pin on my previous post showing power to pin 8. …. I’m not sure if matters but I can’t operate windows with PP while it is still plugged into the RVC .
If I recall, you said that you had swapped out the RVC at some point, is that correct? If so, you might try the other module and see if you get anything on those pins. The windows are on separate relays, probably four total (up & down for each side), so there is not much in common to disable everything. One possibility is a power or ground issue on the coil side of the relays. I originally thought that something was blocking the windows, but the B1402/3 codes indicate that the RVC is trying to move them, just not providing the necessary power/ground for some reason.
If I recall, you said that you had swapped out the RVC at some point, is that correct? If so, you might try the other module and see if you get anything on those pins. The windows are on separate relays, probably four total (up & down for each side), so there is not much in common to disable everything. One possibility is a power or ground issue on the coil side of the relays. I originally thought that something was blocking the windows, but the B1402/3 codes indicate that the RVC is trying to move them, just not providing the necessary power/ground for some reason.
yes I did replace it with another one with the same out-come ,
If I recall, you said that you had swapped out the RVC at some point, is that correct? If so, you might try the other module and see if you get anything on those pins. The windows are on separate relays, probably four total (up & down for each side), so there is not much in common to disable everything. One possibility is a power or ground issue on the coil side of the relays. I originally thought that something was blocking the windows, but the B1402/3 codes indicate that the RVC is trying to move them, just not providing the necessary power/ground for some reason.
I was starting to think the same thing. Ground and power (before the individual fuses) are common to both windows. It is possible that you have a poor ground or you are getting a big voltage drop under load because of resistance in the rear fuse box. If you can remove one of the window pins from the RVC connector, that will eliminate load. You can then back probe the other pin and check for voltage or continuity to ground when you attempt to operate the window. If you get good voltage, replace the pin and back probe it again. If you have low or no voltage, you have some issue on the supply side. If the ground is bad, you should still see voltage on one of the pins when you try to operate the window.
I was starting to think the same thing. Ground and power (before the individual fuses) are common to both windows. It is possible that you have a poor ground or you are getting a big voltage drop under load because of resistance in the rear fuse box. If you can remove one of the window pins from the RVC connector, that will eliminate load. You can then back probe the other pin and check for voltage or continuity to ground when you attempt to operate the window. If you get good voltage, replace the pin and back probe it again. If you have low or no voltage, you have some issue on the supply side. If the ground is bad, you should still see voltage on one of the pins when you try to operate the window.
Hi Mike I received a r230 technician training manual when I bought the car ,I put up I didn’t think anything about , but with dumb luck my cat knocked off my shelf, anyway when I picked it I noticed a section on the roof I glanced through it and found this. My question is will the rear flaps effect my rear window issues, here’s a picture with some notes on it … just so you know I have replaced or checked everything that have been discussed in this thread. Also do you know what @x8/4 conn. Might mean ?
Last edited by hhagens; Jan 14, 2024 at 10:38 PM.
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