toyota highlander, cel, vsc problems

Hi

This problem was posted before but I didn't see what resolved it. The CEL and the VSC lights come on intermittantly after remote start. The customer has brought the vehicle to Toyota and they say their is a load of some sort on one of the Ign wires. This is an Audiovox APS-905 R/S. The wires for the Ign all go straight to the RS with the exception of the second start wire which is wired to activate through a relay. Has anybody else seen this?? If there is a load on the wire the R/S is doing it internally probably for engine monitoring. With this problem happening intermittantly it's difficult to trace. I also have swapped out the R/S to see if there was an issue with it and that didn't make the problem go away.

Thanks
Jon
Traveling Electronics

It could be those problems but, the dealership is telling me it's the park switch. That is consistant. Since I only have a code reader I can only see the code after it's generated. I'm hoping the dealer can put this thing on a real time reader so I can see exactly when this code is being thrown. I have researched the net and found others have had similar issues with Toyota's but have not seen what they did for a reslove. The code is as follows : P0705. The pcm has determined that a malfunction exists in the electrical circuit for the transmission range sensor. (PRNDL input).

What year Highlander ? Did you power up all the IGN & the ACC wires along with the 2nd Starter?

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Jeff
Velocity Custom Home Theater
Mobile Audio/Video Specialist
Morden, Manitoba CANADA

Hi

The Highlander is an '07 and yes all the wiring is hooked up to the IGN switch I checked with Direct Techs, Audiovox and Installogy to be sure.

I think I have a solve for this issue. After talking to Scott at Audiovox he says he has heard of this problem before it doesn't effect all cars. It seems that Audiovox uses a circuit called "crank averaging" on the start wire. In the Highlander this start wire and one IGN wire are hooked to the park position switch. The start wire from the R/S has enough ground potential to make the vehicle think it's in park and in gear at the same time. The P0705 code actually comes up quite a bit in google searches on Toyota's. So, if you hook up the start wiring one way the problem isn't there because the relay keeps the circuit open after crank (2nd start wire) but swapping the two start wires Will cause a check engine light intermittantly.

I have seen a couple of instances when Toyota's OBD have caused CEL's for little or nothing. Very tight tolerances on O2 sensors and such. Makes me feel that Toyota does this type of thing on purpose to get great $$ in the repair department.

Oh well time will tell on this one. It might take a week for the code to pop up again. Until then I'll keep my fingers crossed that it's fixed.

Jon
Traveling Electronics

Looks like you guys already have this one figured out!

Basically, it goes like this:

1. The cars' starter wire(s) rest at ground when the car is in Park or Neutral. When the car is in gear, the connection to the starter solenoid is broken, and the ground goes away.

2. If, for whatever reason, there's a ground on the wire(s) while the car is in motion..........basically, the car "sees" that it's in Park, but that there's a speed signal on the VSS wire.........the car knows this isn't normal, and assumes the PRNDL switch has failed.

NismaX,

What are you using to activate the relay for the second starter wire? Like tonyberg says.......are you using the Audiovox's thick yellow to activate your relay, or the small BLACK/ yelow "pulse during start?"

Also, do you have any kind of anti-grind relay installed?

As I remember it I used the yellow to feed the relay and not the BLACK / YELLOW. Hmmmm so it may be back after all for a little rewire. No there is no anti-grind relay. I only offer such a thing to people that really need it (they ask for such a thing) That isn't a problem I want to repair after the relay cycles on and off over the years and the customer is stuck wondering why they can't start their car.

Wow! you really charged the other shop $565 to repair their work? That's more than they probably made on the whole job. Did they pay you?

Jon

Yes they paid the bill...I work for the toyota dealer...no pay...no car

Sitting in the parking lot of a Toyota dealer right now, having just fixed two more of these today. Same code P0705 on both.

1. '07 Camry. The car's two starter wires were jumped together, instead of wired separately with a relay.

I was surprised at this, because I've seen hundreds of Camrys before with the starter wires jumped together, with no problems.

At least this one was an easy fix.

2. '07 RAV4. Code Alarm CA500, but that's the same as Audiovox. It was another company that did the original job.

The second starter wire was set up with a relay, but they jumped onto the remote starter's high-current starter output, as in NismaX's installation.

This would have also been an easy fix, except:

A) The original installer chose to wrap pretty much EVERYTHING in layers and layers of black tape, leaving a big mess to dig through to reconfigure just a couple of wires, and:

B) The car's owner not only smokes excessively, but seems to think the steering column cover makes a good ashtray, and the driver's floor mat a great place to pour coffee.

When I popped off the lower dash panel, literally half a cup of ashes fell all over the floor and carpeting, sending up a nice dust cloud too. Gross. Especially for an almost brand new car.

But I charged extra.