Intermittent Starter abort

[mattmatt14]

Hello everyone. I'm having some trouble diagnosing an issue on a friend's truck. It's a 2010 1500 5.7 2wd. Note: apparently the engine was replaced with a used one, there was an aftermarket alarm system that was removed, the ckp was replaced, and the starter is new.

The issue: when cranking, intermittently, the starter bumps the engine a few degrees and then aborts. It bumps the same amount of rotation every time. If I attempt to start the truck enough, it will eventually turn over and start. When it does start, it runs perfectly. There are no codes in the PCM or wcm. I have a reverse light circuit open code and a wiper code in the tipm.

If I jump the starter relay and have someone turn the key to start, the truck starts every time. (Me thinking it's either PCM ground supply or tipm power supply to the relay coil)
If I supply external ground, bypassing the PCM relay control, it still intermittently bumps. (Ok it must be the tipm)
If I supply external power, bypassing the Tipm relay control, it still intermittently bumps.
If I disconnect the starter solenoid, the PCM and tipm will energize the relay every time.
So the relay control cuts out immediately only when the engine starts to spin. Why?

When I monitor the pids in the tipm I don't see anything out of the ordinary. The transmission range sensor shows proper position and switches fine, the ignition switch also shows proper position and switches fine and the truck is detecting the key. No security light on or flashing. I had the tipm and PCM apart, all the connections look good. Internally, the boards look fine with no corrosion, damage, or smell.

If anyone has had this issue or if anyone has a direction I should look towards I would appreciate the assistance.

 

[Ken226]

Have you tried swapping in another relay?

 

[mattmatt14]

Yes. I've tried a different relay, different battery, and cleaned all of the grounds.

 

[Ken226]

Yes. I've tried a different relay, different battery, and cleaned all of the grounds.

In that case, the next logical place to look is the TIPM.

In a 2013+, the BCM and wiring from the BCM to the Power Distribution Center would also play a role and be in the equation.

But in your 2010, the TIPM handles all those functions and there is no BCM.

Pull the TIPM then inspect it and the connectors for corrosion. It's a common issue. Especially if you live in the northeast.

 

[mattmatt14]

In that case, the next logical place to look is the TIPM.

In a 2013+, the BCM and wiring from the BCM to the Power Distribution Center would also play a role and be in the equation.

But in your 2010, the TIPM handles all those functions and there is no BCM.

Pull the TIPM then inspect it and the connectors for corrosion. It's a common issue. Especially if you live in the northeast.

I've had the TIPM removed already and pulled it apart. I did not see any sign of damage. I also inspected the connectors and the pins are all clean and still in position. I know about the TIPM issues with these trucks but I'd just hate to throw a part at it and it not be it.

 

[jws123]

I've had the TIPM removed already and pulled it apart. I did not see any sign of damage. I also inspected the connectors and the pins are all clean and still in position. I know about the TIPM issues with these trucks but I'd just hate to throw a part at it and it not be it.

The ignitions fail often if you wiggle the key or hold it up or down will it start? also you can repair your TIPM if it winds up being the issue just solder in a new relay.

 

[mattmatt14]

The ignitions fail often if you wiggle the key or hold it up or down will it start? also you can repair your TIPM if it winds up being the issue just solder in a new relay.

I will try messing with the ignition again. When I was monitoring the pids it would show proper position whether the truck would start or not. I'm leaning towards internal relay on TIPM but just not 100%.

 

[Wild one]

I will try messing with the ignition again. When I was monitoring the pids it would show proper position whether the truck would start or not. I'm leaning towards internal relay on TIPM but just not 100%.

If it starts everytime when you jump the relay pins ,it's probably the relay itself. I'm not overly familiar with the fuse box on a 2010,but if the relay just plugs in,did you try swapping another relay in place.

 

[Ken226]

How does the relays fitment into the socket feel? Make sure the terminals in the relay socket are tight, as spread terminals that don't grip the relay spades can mimic a bad relay.

 

[mattmatt14]

How does the relays fitment into the socket feel? Make sure the terminals in the relay socket are tight, as spread terminals that don't grip the relay spades can mimic a bad relay.

The relay makes good contact. When I had the TIPM disassembled I put the relay back into the bare pins and could feel and see that it was tight and the contact was clean.

 

[mattmatt14]

If it starts everytime when you jump the relay pins ,it's probably the relay itself. I'm not overly familiar with the fuse box on a 2010,but if the relay just plugs in,did you try swapping another relay in place.

Yes I tried a swapping another relay, same symptoms. Pins are tight and contacts are clean.

 

[mattmatt14]

The thing is that I am able to get the truck to start every time by bypassing the relay control (pins 85 and 86) and jumping power from 30 and 87 while holding key in start. That leads me to think something is wrong with either PCM or TIPM.

But on the other hand.... If I disconnect the circuit feeding the starter solenoid signal, the truck will consistently switch the relay on every time without me having to jump it. Which would mean the PCM and TIPM are able to control the relay coil just fine but the difference here is that the engine doesn't spin or no load on starter solenoid signal circuit because it's disconnected.

I'm unfamiliar with the interaction between the PCM and TIPM on these trucks so I am thinking two things:
1- PCM seeing some kind of a bad input immediately after the engine starts to rotate and cutting the signal to crank or
2- the starter solenoid signal circuit is drawing too much current? But how would that circuit even be monitored by a control module or how would it see high current when it's on the switched side of the relay? I also ran a jumper from the relay pin output to the starter solenoid signal pin and still had abort symptoms. Could it possibly be TIPM internal starter relay intermittently failing to stay on but only when starter solenoid signal circuit is connected? But if it were this, I would think that the starter command would drop out at varying rotations. What I mean by that is that the starter command aborts after the same amount of engine rotation every time. Always around 2 degrees of rotation.

Forgive me for rambling on here, I am kind of typing as I think of other possibilities.

 

[Wild one]

The thing is that I am able to get the truck to start every time by bypassing the relay control (pins 85 and 86) and jumping power from 30 and 87 while holding key in start. That leads me to think something is wrong with either PCM or TIPM.

But on the other hand.... If I disconnect the circuit feeding the starter solenoid signal, the truck will consistently switch the relay on every time without me having to jump it. Which would mean the PCM and TIPM are able to control the relay coil just fine but the difference here is that the engine doesn't spin or no load on starter solenoid signal circuit because it's disconnected.

I'm unfamiliar with the interaction between the PCM and TIPM on these trucks so I am thinking two things:
1- PCM seeing some kind of a bad input immediately after the engine starts to rotate and cutting the signal to crank or
2- the starter solenoid signal circuit is drawing too much current? But how would that circuit even be monitored by a control module or how would it see high current when it's on the switched side of the relay? I also ran a jumper from the relay pin output to the starter solenoid signal pin and still had abort symptoms. Could it possibly be TIPM internal starter relay intermittently failing to stay on but only when starter solenoid signal circuit is connected? But if it were this, I would think that the starter command would drop out at varying rotations. What I mean by that is that the starter command aborts after the same amount of engine rotation every time. Always around 2 degrees of rotation.

Forgive me for rambling on here, I am kind of typing as I think of other possibilities.

Your easiest fix on a 17 year old truck,would be to run a remote push button switch inside the cab that jumps relay pins 87 and 30,then train the owner to turn the ignition On before hitting the push button starter switch.

 

[04fxdwgi]

Have you tried pulling any codes?
If the crank or cam position sensor isn't sending proper signal, that can happen.

 

[Tominator223]

Could still be a bad ground cable. Even after cleaning the grounds. The cable could have corrosion inside it. Run a small 10g ground just to see. I’m not sure on the 10 tipm. But my 04 tipm has 3 relays inside that do need soldered. Not to hard just need an iron that gets over 900*. The key switch in my 04 actually has the electric switch behind it under the cover on the bottom.

 

[04fxdwgi]

1st go to is always load test battery and check all grounds and B+ connections and cable condition, before diving into things too deeply. Be surprised how many times that is it..