APPARENT MALFUNCTIONING OF AMS IGNITION LOCK MOTOR 4270P ON WINDSHIELD SHADES

Symptoms:

When pressing the dashboard switch, the shade moves only 1 inch in either direction, then stops and one must press the dashboard switch again to move another inch.

The shade not working properly but when one reprograms the limits, shade starts working fine for a while then problem occurs again later.

When one attaches the programmer and then presses top buttons on the programmer, the shade moves an inch, then stops and one must press programmer button again for the shade to move again.

Cause:

In all probability, the issues listed above are likely caused by either a defective motor or a vehicle wiring problem. If the motor is broken, an exchange is required, however, in case of a vehicle wiring issue a motor exchange will not solve the problem. Intermittent operational problems may occur as wires short out intermittently which requires a more thorough investigation.

Note 1:

The most possible cause of a wiring issue and having intermittent symptoms as a result of that could be the followings:

• A loose connection at the wires to the back of the dashboard switch/relay, or at the wire connectors of the shade to vehicle wiring.

• The insulation of one of the wires from the dashboard switch to the shade has been stripped in one area possibly due to a sharp metal edge or corner. As the bare wire comes in contact with the metal chassis of the vehicle it shortens out for as long as the bare wire touches the frame. This results in high transition noise signals that confuse the motor programming unit, and as a result stops the motor to function properly. Such intermittent and brief shortages may not trip the fuse but those shortages negatively affect the motor memory settings.

Note 2:

Due to the very nature of a loose connection or infrequent shortening as the wire connects with the chassis intermittently, identification of this problem is difficult.

This also explains why in some instances, the problem seems to resolve by itself (or resolved after motor replacement) temporarily before problem returning again.

Here are the 3 easy ways to find out whether it is a bad motor or a vehicle wiring issue:

1. In instances where the vehicle is fitted with a motorized double roller shade, and the issue appears on one motor only. For a diagnosis, follow these steps:

   • On top of the head crown of the motor there is a black Molex connector for a cable with 3-wires (red/green/blue). This Molex connector has a tongue; press it and pull the Molex connector out.

   • Pull the Molex connector out from the second shade as well, swap the cables and reconnect both shades.

   • If the problem has switched from one shade to the other and now the shade operates well then, the vehicle has a wiring issue and both motors are operating properly. However, if the problem continues with the originally shade after switching the input cables, then the problem is with the motor which needs to be exchanged. This way is very useful if problem is intermittent and you need to wait for a week to see if it happens again.

2. With this method one uses an extra cable (red/green/blue wires) with a Molex connector on the cable as a diagnostic tool.

   • On the non-functioning shade, remove the installed Molex connector and connect this cable to the Molex connector. Now one has 3 exposed wires: red/ green/blue.

   • Leave the red wire not connected to anything.

   • Connect the green and blue wires to a 12VDC supply source like a battery, or cigarette lighter. Polarity does not matter.

   • Using the programmer, first press delete button on programmer to delete old programs and now one should be able to move the shade up and down using programmer buttons. If the shade operates smoothly up and down, then the motor is ok and there is an issue with wiring. If the shade does not run or runs with stoppages then there is an issue with the motor.

3. In case the installed Molex connector on the crown of motor is not accessible, or one does not have an extra cable with Molex connector, follow this step:

   • On the problematic shade, follow the 3-wire cable (red/green/blue) from the motor which goes behind the side cover. Now pull out the cable, remove the tie-wrap around the cable bundle and disconnect the 3 wires from vehicle wiring (Do not cut wires); now the 3 wires of the shade are free in hand.

   • Leave the red wire not connected to anything.

   • Connect green and blue wires to an external power supply (12VDC). Polarity does not matter.

   • Using the programmer, press delete on programmer to delete old programing. Now one should be able to move the shade fully up and down using programmer buttons.

   • If the shades operate smoothly up/down, then motor is ok but there is an issue with wiring. If the shade does not run/run with stoppage issue then there is an issue with motor.

A helpful note regarding programming:

After bypassing the vehicle wiring and once a reliable 12V source has been connected directly to the green and blue wires of the motor (red wire floats), the left-hand blue light on the programmer should be solidly on. Now press DELETE on the programmer until the other light goes on, and then press the left and right buttons on the programmer to move the shades up and down. If the shade moves smoothly up and down, then the motor function properly and do not need to be replaced.

A final note on older shades/motors:

On legacy-AMS shades we used a big spring on other side of tube to prevent the shade from unravelling and obstructing the driver’s vision in the unlikely event of a motor shaft failure. On newer generation shades, AMS stopped using springs as we implemented a safety feature which was integrated in the new motor generation. In some instances, motor stoppage might be caused by spring binding/ceasing. In these instances, one will hear a noise from the other side of tube when the shade is trying to move or moving with problems. In these instances, we offer a spring bypass kit. For more information, please refer to our note QRG 20.