Need to troubleshoot failure of convertible top to close (at all) except manually. We bought it used and everything tested well. We got home and tried to put the top down for the night, it moved about 18 inches and stopped. There is not even a motor noise like it is trying to close. Where do I start?

There are only Two things in the right rear the pump motor and the top ajar switch. This sounds like the motor is locked up or the top is jammed or going the wrong way. First disconnect the motor and if the noise stops it's the hydraulic unit trying to move the top watch the top to make sure it's going the right way, the top ajar switch could be bad. If you're confident in the hydraulic unit and motor the only thing left is a jammed top, a bad connection at the hydraulic unit, or the top ajar switch. I hope this helps. Take care.

Principles of Operation
Convertible top operation is controlled by the smart junction box (SJB). When the convertible top raise/lower switch is operated, the SJB commands the front and rear windows to the full down position. Window operation is disabled while the convertible top raise/lower switch is being operated. When the SJB receives a full down input for both rear windows, it commands the appropriate relay closed to raise or lower the convertible top. If the SJB does not receive a full down input signal for both rear windows, the convertible top operation is disabled.

The convertible top hydraulic system uses a 12 volt reversible pump and motor assembly. When active, the pump uses hydraulic pressure to extend the hydraulic lift cylinders to raise the convertible top, or retract the hydraulic lift cylinders to lower the convertible top. The convertible top motor/pump assembly is equipped with a thermal circuit breaker. The circuit breaker typically resets after 5 minutes depending on the ambient temperature. The thermal circuit breaker cannot be repaired and must be installed as a unit with the motor/pump assembly. In the event of a hydraulic system failure, the convertible top cannot be operated manually.

Inspection and Verification

1. Verify the customer concern.

1. Visually inspect for obvious signs of mechanical or electrical damage.

Visual Inspection Chart Mechanical Electrical

• Convertible top brackets and frame
• Convertible top latches
• Convertible top pump and motor assembly
• Hydraulic lift cylinders
• Hydraulic lines

• Bussed electrical center (BEC) fuse(s):
  • 13 (40A)
  • 51 (10A)
• Circuitry
• Convertible top pump and motor assembly
• Convertible top ajar switch
• Convertible top switch
• Connector(s)
• Convertible top raise relay
• Convertible top lower relay
• LH or RH rear power window motor
• Smart junction box (SJB)
• BEC

1. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.

1. If the cause is not visually evident, connect the scan tool to the data link connector (DLC) and select the vehicle to be tested from the scan tool menu. If the scan tool does not communicate with the vehicle:
   • check that the program card is correctly installed.
   • check the connections to the vehicle.
   • check the ignition switch position.

1. If the scan tool still does not communicate with the vehicle, refer to the scan tool operating manual.

1. Carry out the scan tool data link test. If the scan tool responds with:
   • CAN or ISO circuit fault; all electronic control units no response/not equipped, refer to Section 418-00 .
   • No response/not equipped for SJB; refer to Section 419-10 .
   • System passed, retrieve and record the continuous diagnostic trouble codes (DTCs), erase the continuous DTCs, and carry out self-test diagnostics for the SJB.

1. If the DTCs retrieved are related to the concern, go to the Smart Junction Box (SJB) Diagnostic Trouble Code (DTC) Index.

1. If no DTCs related to the concern are retrieved, GO to Symptom Chart .
2. Smart Junction Box (SJB) Diagnostic Trouble Code (DTC) Index DTC Description Source Action B1141 Convertible Top Full Down Position Switch Circuit Failure SJB Go To Pinpoint Test E . B1142 Convertible Top Full Up Position Switch Circuit Failure SJB Go To Pinpoint Test E . B1402 Driver Power Window Down Switch Circuit Failure SJB Go To Pinpoint Test A . B2068 Convertible Top Up Output Circuit Failure SJB Go To Pinpoint Test A . B2069 Convertible Top Down Output Circuit Failure SJB Go To Pinpoint Test A . B2481 Convertible Top Up/Down Switch Fault SJB Go To Pinpoint Test A . B2578 Passenger Power Window Down Switch Circuit Failure SJB Go To Pinpoint Test A . All Other DTCs - SJB Refer to Section 419-10 .
3. Your best bet ,take it to a qualified repair shop !

You will need the system tested for both electrical and mechanical problems with the transmission by a qualified expert it requires special tools and knowledge to perform the testing. At that high of milage it could have allot of problems. It is not a "do at home" job. Sorry.

Because of lack of information (data) about your inspection, it is hard to tell where the failure is.
For more information about changing catalytic converter. The price can be 10 times different.
The highest quota I got was over $1400 (the golden smog station), the lowest was below $200 (found by state division where I asked for compensation due to old car -- since I cannot go there directly, I paid $325 fro an agent to do it). Dealer was asking for $700.
After changed a home genie catalytic converter, which worked better then the original manufactured till car is dead in another 10 years, I brought it back to the golden smog station for free re-test. The technician did not believe that is a new, and inspected to verify that is true.
This homegenie catalytic converter passed a number of smog tests till car is dead after another 10 years.
BTW, the original manufactured catalytic converter failed on the very first smog check at year 6 or 7 after can was bought, so it is possible you had a failure catalytic converter, but inspection result may tell.

look around your convertible top and its like you have problem with the black seal some thing there make your convertible top not close good . try look again and i hop you found the problem . look good .let me know .

Hey there, I have experienced the same problem. You need to reengage both motors if you have disengaged them pulling the lever undernearth the rear driverside seat. Make sure to put the black lever back under the seat to the position before pulling on it.

You should have the top in the down position before engaging the motors back in place.

To engage the motors: The motors are located under the carpet in the trunk on the driver side. There are two black clips you will need to remove in order to pull the carpet back. One of the motors is located near the taillight. This motor is responsible for the storage lid cover. The motor that is located further in the drunk is the motor for the fabric top to move up and down. Make sure to firmly press these motors back into place. They should not move.

Once you have engaged the motors, go into your car put the key into the ignition and have the convertible top button pressed up (meaning to close the top), move the key to the accessory positio and hold it for 10-12 seconds. You will finally see the trunk lid get pulled closed. The car will now attempt to completely close the lid. If your motors are working fine it will close. If your only intention is to get the lid to close on it's own it should be accomplished.

Good luck!

I just bought a 1996 328iC (the "C" is for convertible). I bought the car with the knowledge that the roof needed a motor replacement (~$300 for the part alone + ~1-2 hours labor) and that I would need to open and close the roof manually if I wanted to take advantage of the convertible part of the car.

After some trial and error, I figured it out and now it takes me <30 seconds to open or close the top (manually). Note: my top is a semi-electric roof, which I think is what came on the 328iC, you have to lock into place after you close it.

Here's what you do:
1- open all of the windows
2- unlock the roof by turning the latch between the sun visors.
3- push the front of the roof towards the rear of the car - be sure to push in the middle of the roof, where the latch is.
4- lift the back of the roof up off of the roof storage compartment
5- while holding the back of the of the roof up, lift up the roof storage compartment door
6- let go of the back of the roof so that it drops right into the storage compartment
7- push the rest of the roof into the storage compartment
8- close the storage compartment door.

To close the roof, follow the steps above in reverse order. Remember: this is a German car, so you use a little bit (or a lot) of force and you won't hurt it (I think it actually likes it ;-D ).

Good Luck!!!

Roman