Top News

AUTO ADVICE: Window won’t go up; check-engine notice

- 123RF Stock Photo

Question & Answer

Q: Could you provide me some information on my old 1988 Toyota 4 Runner. I can not get the back window to go up and down without jumping out the motor directly from a battery. I have checked the wiring and can not find anything broken or worn. Any information would be helpful.

A: The rear power window on your 4 Runner can be controlled by either the console up/down switch or the back door control switch. Both of these switches provide a ground to different terminals on the rear power window relay. Because neither switch works, I would say the problem isn’t in the switches or the wiring to the relay. I would start my testing at the relay. It is located behind the left rear quarter panel trim next to the rear seat and controls the rear power window and rear wiper motor.

Power should be at terminals 6 and 8 of the relay. If the wiper doesn’t work too, check the fuse/relay centre under the left dash for bad fuses or circuit breakers.

Grounding terminal 11 of the relay with everything connected should make the window go down. Grounding terminal 12 should make it go up. If this doesn’t work, the relay should be the culprit.

If the relay tests OK, then the back door lock detection switch or the wiring to it may be open in the tailgate. This switch opens the ground circuit for the control switches so the window can’t be operated when the doors are locked. Start testing at the relay thought. It is the easiest place.

Q: I drive a 2005 Dodge Magnum. The car is running great. It has 174,000 km on it. However, in the last month the check-engine light has been coming on. This light only comes on and stays on (but only occasionally) when we put the key in the ignition to start the car.

We know when it will happen because when you start the car, it starts up right away, hesitates for about two seconds, then starts revving normally and the light doesn’t go off. Every now and then the airbag light stays on after turning on the car but will turn off when you turn off the car and restart it. However, the check engine light will remain on until the mechanic turns it off.

The light never comes on while we are driving the car. I could drive the car from Winnipeg to Brandon and there would be no light, however, if I turned the car off and then started it again and it hesitated, the light would come on and stay on. When this first happened, I went to our mechanic whom I trust with my life, and he checked the car out and the code 1698 came up.

Dealer says code is inconclusive, nothing wrong, bring it back ... again, again and again. Is the car safe to drive in the meantime. As I mentioned, it is running perfectly normal, no problems, changes gears appropriately, etc.

Help please.

A: The code 1698 may be the key to your problem. It is a communication code indicating there is a loss of communications with the transmission control module on the CCD (Chrysler Collision Detection) bus.

This bus is a data communication network between modules on your vehicle and has nothing to do with vehicle collisions. Instead, it allows communications between modules without data collisions.

The CCD bus uses a twisted two-wire network. The wires are twisted to reduce the electromagnetic interference. When one module sends information, all modules receive the information, but only some modules use it. I suspect you have a loose connection on the CCD bus that is preventing data communications.

The Air bag light sometimes comes on if the instrument cluster doesn’t see communications from the air bag module. A code is set because the powertrain control module is temporarily loosing communications with the transmission module. The check engine light doesn’t go out because of the programming in the powertrain module related to emissions.

The dealer may have to check CCD bus connections at all modules and the wiring harness on the vehicle to locate the problems. If no problems are found, the Transmission computer or powertrain computer may have to be changed.

Jim Kerr is a master automobile mechanic and retired teacher of automotive technology. Send your questions for Jim via email or mail them to: Herald Wheels, 2717 Joseph Howe Drive, P.O. Box 610, Halifax, N.S. B3J 2T2

Recent Stories