Hello All,

First post here , as our 07 Caravan has ran great up until yesterday morning .

Its an 07 with a 3.3 . My wife went to start it yesterday and it just cranks and cranks with no start .

I started doing some trouble shooting and found out that there is no spark getting to the spark plugs , verfied with a timing light and also the grounding a spark plug while cranking trick. Crap ! Something is definately wrong.


I went a got and got a loaner scan tool , I check it every now and again and there is usually no codes. However it is now throwing the following codes.


P1684 - The battery has been disconnected within the last 50 starts
P0685 - ECM/PCM Power Relay Control Circuit/Open
P0688 - ECM/PCM Power Relay Sense Circuit/Open


swapped in a battery from my boat , no change...... (original and boat battery are good and reading above 12 volts)

So I did a little googling last night and there were several posts about these codes leading to the automatic shut down relay , or ASD. It pops up alot online and seems to be faily problematic.

Thinking it might just be the relay itself , I then swapped out several good relays into the ASD that were all good and that did not change anything.

also while searching I found several posts about "jumping" the relay between pins 30 and 87 on the ASD realy , so I figured I would try that to at least get the van into the garage . This DID work ! The van fires right up and seems to be "normal" when I jump between those 2 terminals.

So now I have the van in my garage but it will not start unless this jumper is put in. I looked on the back of the fuse box for any loose wires and everything looks great back there. I am stumped now and need some help or direction

So I have a few questions ......

Why is the computer or whatever not energizing this relay ?

Is it possible that a crank sensor is bad and doesnt realize that the engine is turning when I crank it over ? Would there be some other codes ?

I dont want to just start tossing parts at it , as that never fixes the problem and I dont want to just leave that jumper in place and call it good and fixed .

Anyone ran into this problem before ? and what was the actual fix?


Sorry for the book I wrote , and Thank in advance for any help / guidance.

 

Sorry no one has been able to help you yet. I am not a mechanic or expert, but I do have a service manual for my '01 so I could become dangerous.


P0685 and P0688 both are pointing to bad connections between the PCM and the ASD relay.


You may have a bad wire between the PCM and the ASD relay. The relay gets 12 volts from Fuse 6 (30 Amp) there in the PDC. That's the same voltage that you jumpered from pin 30 to pin 87 to get it to start. So, we know the relay is getting power.


When you turn the key on, the relay is turned on by the PCM grounding pin 85 on the relay. The wire comes from PCM connector 3, pin 3 (AUTOMATIC SHUTDOWN RELAY CONTROL). Get a meter and check this connection from one end to the other. It is a dark blue wire with a yellow stripe.
The other connection is from the ASD relay pin 87 to the PCM connector 3 pin 12 (AUTOMATIC SHUTDOWN RELAY OUTPUT). It is a dark green wire with an orange stripe. This is the same circuit that goes to the ignition coil and the fuel injectors.


You have eliminated the relay as being the cause of the problem by swapping it with other known-good relays. Check where the relay plugs in for corrosion or otherwise bad connection.
Hope it's a fixable connection problem. The last option seems like another PCM.

 

It's almost been 2 weeks, and we're dying to know how it's progressing. When you get time, please tell us. There's somebody else out there who needs to know how to fix their problem, plus it encourages others to help.

 

CTION APPLICABILITY
3 NOTE: Inspect the ASD Relay fuse located in the IPM. If the ASD Relay fuse
is open, repair the cause of the open first before continuing. Inspect theASD
Relay Output circuit for a short to ground for the cause of the open fuse.
Turn the ignition off.
Remove the ASD Relay from the IPM.
Turn the ignition on.
Using a 12-volt test light connected to ground, probe the Fused B+ circuit in the IPM.
Does the test light illuminate?
All
Yes ! Go To 4
No ! Replace the IPM Fuse & Relay Center.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
4 Turn the ignition off.
Remove the ASD Relay from the IPM.
Turn the ignition on.
Using a 12-volt test light connected to 12-volts, probe the ASD Relay Control circuit
in the IPM.
With the DRBIIIt, actuate the ASD Relay.
Does the test light flash on and off?
All
Yes ! Replace the ASD Relay.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No ! Go To 5
5 Turn the ignition off.
Disconnect the IPM C3 harness connector.
Turn the ignition on.
Using a 12-volt test light connected to 12-volts, probe the ASD Relay Control circuit
in the IPM harness connector.
With the DRBIIIt, actuate the ASD Relay.
Does the test light flash on and off?
All
Yes ! Replace the IPM Fused & Relay Center.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No ! Go To 6
6 Turn the ignition off.
Disconnect the IPM C3 harness connector.
Disconnect the PCM harness connector.
Measure the resistance of theASD Relay Control circuit between the IPM C3 harness
connector and the PCM harness connector.
Is the resistance below 5.0 ohms.
All
Yes ! Go To 7
No ! Repair the ASD Relay Control circuit for an open.
Turn the ignition off.
Disconnect the IPM C3 harness connector.
Disconnect the PCM harness connector.
Measure the resistance of the ASD Relay Control circuit in the IPM C3 harness
connector to ground.
Is the resistance below 5.0 ohms.
All
Yes ! Repair the ASD Relay Control circuit for a short to ground.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No ! Go To 8
8 If there are no possible causes remaining, view repair. All
Repair
Replace and program the Powertrain Control Module Module in
accordance with the Service Information.

 

Master Tech: Does the DRBIII test the relay through the PCM connections to the IPM? I bet it wouldn't work even if he could get a DRBIII.

Running with the bypass jumper proves that the connection from relay pin 87 to the engine is intact. Does the PCM do anything with the ASD Sense signal?

The truck runs with the ASD bypass in, so I would assume that the cam and crank inputs needed by the PCM are there.

Can we assume that the codes are saying that the PCM can't see the ASD Relay?


I don't have an '07 manual, so the connector references that I gave him are probably wrong. Can you tell us the correct connector and pin numbers?

 

Sorry I was away. The DRB 3 can actuate the relays, I would remove the IPM up and look at the connections. Make sure a pin or pins are not either push out or has turn green.

 

P0688 code. Here is some more information.

NOTE: Inspect the ASD Relay fuse located in the IPM. If the ASD Relay fuse
is open, repair the cause of the open first before continuing. Inspect the ASD
Relay Output circuit for a short to ground for the cause of the open fuse.
NOTE: Diagnose P685 - Auto Shutdown Relay Control Circuit first if set
along with this DTC.
With the DRBIIIt, erase the DTC.
Attempt to start the engine. If the engine will not start, crank the engine for at least
15 seconds. It may be necessary to repeat several times.
Does the DTC reset.
All
Yes ! Go To 2
No ! Refer to the INTERMITTENT CONDITION symptom in the
Driveability category.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
2 Attempt to start the engine.
Does the engine start.
All
Yes ! Go To 3
No ! Go To 5
Turn the ignition off.
Disconnect the PCM harness connector.
Disconnect the IPM C4 harness connector
Measure the resistance of the ASD Output circuit between the IPM harness
connector and the PCM harness connector.
Is the resistance below 5.0 ohms?
All
Yes ! Go To 4
No ! Repair the ASD Relay Output circuit for an open.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
4 If there are no possible causes remaining, view repair. All
Repair
Replace and program the Powertrain Control Module in accordance
with the Service Information.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
5 Turn the ignition off.
Install a substitute relay in place of the ASD Relay.
With the DRBIIIt, erase DTCs.
Attempt to start the engine.
With the DRBIIIt, read DTCs.
Does the DTC reset?
All
Yes ! Go To 6
No ! Replace the ASD Relay.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
6 Turn the ignition off.
Remove the ASD Relay from the IPM.
Using a 12-volt test light connected to ground, probe the Fused B+ circuit in the IPM.
Does the test light illuminate?
All
Yes ! Go To 7
No ! Replace the IPM Fuse & Relay Center.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
7 Turn the ignition off.
Remove the ASD Relay from the IPM.
Disconnect the PCM harness connector.
Disconnect the IPM C4 harness connector.
Measure the resistance of the ASD Relay Output circuit between the IPM harness
connector and the PCM harness connector.
Is the resistance below 5.0 ohms.
All
Yes ! Go To 8
No ! Repair the ASD Relay Output circuit for an open.
NOTE: Ensure the IPM C4 harness connector is connected to the IPM.
Turn the ignition off.
Disconnect the PCM harness connector.
Measure the resistance of the ASD Relay Output circuit between the IPM and the
PCM harness connector.
Is the resistance below 5.0 ohms?
All
Yes ! Replace and program the Powertrain Control Module in accordance
with the Service Information.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No ! Replace the IPM Fuse & Relay Center.