Pelican Parts Forums - Replacing Battery Cable from Front Trunk to Starter Motor

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Agree big cable not likely culprit
Also would carefully clean and inspect the grounds
On the older cars people often install a "hot start relay" to solve this problem

Oh and the Denso is not a crappy starter. The motor is first rate but the contacts in the solenoid are prone to burning and need replacement every 100k miles or so. Easy fix in a Porsche...PIA in a Lexus where the starter resides in the valley of the V8

NEVER short out a battery! My dad hand built parts for Voyager (still working!) and wanted to show me a little lesson. We had an old "dead" 12v battery in the basement so Dad took a pipe and shorted it

It EXPLODED- Acid everywhere! Luckily no one lost their vision or WORSE.

Never short a battery! There is so much current it's amazing (even a "dead" one)!

Quote:

Originally Posted by polizei (Post 6642335)

Guys - I know, I know... replacing the trunk-to-starter battery cable is a last resort. Please read on.

I've been encountering sporadic no start issues over the past several months and have had to jump start the car about 7-8 times when in a pinch. My car has visited the mechanic on 3 occasions because of the no start issue. New battery, 2 new start motors, cleaned batter connectors and eliminated all corrosion, and we're still getting no start issues. My mechanic has checked and rechecked that the battery holds a charge, the starter motor is good and the battery is properly grounded.

My mechanic narrowed it down to the trunk-to-starter battery cable and suspected that it was shorting out in a particular section. He tried tugging on the cable from the front trunk as well as from the starter motor, under the no-start condition, and still nothing. Then he removed the petal cluster, tugged the cable and it fired right up! :confused: He's concluded that a section of the cable that runs from the back of the gas tank, through the petal cluster and into the tunnel must be shorting out. He's recommended replacing the entire cable to fix the issue.

After reading several old threads in this forum, I specifically asked if trimming the cable near the front and replacing the connectors would be a good first step. He explained that because he's isolated the short to being near the petal cluster that trimming the front will likely do nothing.

He's a very honest and fair mechanic, and I'm inclined to move forward. He said that while my engine is being rebuilt over the next few weeks that it would be a good do-it-yourself project since it's fairly time-consuming. Since the price of a new factory cable is about $160, he mentioned that I could make my own cable and that it should be the appropriate gauge and be both insulated and intended for automotive use. Can anyone recommend what type of cable to use? Where can I source new connectors that work with a factory starter motor?

Thank you!

Sorry, but if that cable were shorted you would have already had a visit from the local first department. Has the chassis grnd connection for the negative side of the battery been unbolted burnished...??

Have you confirmed that the starter bendix solenoid is getting power...?? Some cars require that the clutch pedal be depressed in order to get power to the starter solenoid.

I just wanted to follow up on this thread. Since the engine is out and I've had ample time on mine hands waiting for the rebuild to be completed, I decided to move forward with replacing the positive battery cable from the battery to the starter motor.

This is a very easy project if the engine is out:

1. Disconnect the positive cable to the starter motor from the battery.

2. From the main cabin, remove the carpet and board near the petal cluster.

3. Disconnect the LARGE vacuum line running from the center console (low end) toward the brake booster (high end)

4. Cut the old positive battery cable that runs behind the petal cluster, separating the old cable into two pieces:

Battery to Petal Cluster
Petal Cluster to Starter Motor

5. Solder new cable to the end of the *Petal Cluster to Starter Motor* cable you just cut.

6. From the rear engine bay, find the end of the old cable that connects to the starter motor and trace the cable to where it enters the cabin. Remove the rubber grommet that seals the cable where it enters the cabin.

7. Lie back, put your feet up the rear sway bar and pull the old cable toward the rear of the car. Continue pulling until you see the new cable and leave enough slack to connect it to the starter motor.

8. Two options here:

Remove the old *Battery to Petal Cluster* cable by pulling from the front truck. Then fish the new cable from near the petal cluster into the front trunk near the battery (what I did)
Or solder the old *Battery to Petal Cluster* cable to the new cable, and pull from the front trunk

There's not a lot of space to solder near the petal cluster, so I decided to just try fishing the new cable into the front trunk. Depending on the type of cable you have, it may want to bunch near the gas tank once you fish it toward the front trunk.

I don't know if this will solve my problem until the engine is back together, but it was easy enough to do with the engine out. Plus it's more culprit to eliminate as I chase down this no start issue!

Thanks for your help guys, and a special thanks to nineball for the cable!

Quote:

Originally Posted by Grady Clay (Post 6642449)

I agree. The B+ cable is an improbable candidate.

Have you cleaned and tightened both ends of the ground strap from the front of the transmission to the chassis?
If it is corroded, replace it.

Best,
Grady

+1 on this..................I have fixed two "non-starters" in as many years by cleaning and tightening both ends of this ground strap. Make sure that you are down to bare metal on the strap and mounting areas (you can check this by using your jumper cables to jumper from the chassis ground lug (where the battery grounds to the chassis) to the starter body (chassis ground at the starter) This effectively jumpers across the existing ground strap and provides a direct ground path from the battery to the starter.

. .......also , you can check if your cable is shorted to the chassis, by disconnecting both ends and then, using an ohmmeter, measuring to see if there is continuity between the cable and the chassis (chassis ground)

regards,
Al

Some years ago while on a road trip I stopped at a Burger King in a small town midway through Nebraska. Upon returning to car to press on toward Omaha, the starter was flat dead, no crank, no click, no nothin'. I waited three and a half hours for AAA before I called back and they had lost the roadservice ticket during a shift-change. While on hold I did the ol' Hail Mary drill, turned the key, and it fired right up... bing, back on the road lickety split. Upon arriving outside Omaha, I stopped at a buddy's place,, killed the car, turned the key again, and nada. In the a.m. it cranked over and I drove to the Porsche Dealership, where they replaced the starter & solonoid. It worked okay until I got back home to Calif, whereupon it reverted to the old, clearly heat sensitive, scenario... after a long drive, something went open. Took it to local dealer, and they replaced the starter & solonoid once again (still warranted from Omaha), and now it's 14 years later with nary an issue. Perhaps the local mechanic routinely cleaned the ground where the Omaha dude didn't, or perhaps there's a cadre of OEM starters out there with heat sensitive windiing issues, I can't say. What I can stipulate to is that I've never seen an intermittant open in a large gauge cable that didn't show signs of severe corrosion at the connector. Just sayin'.

Hope you fixed the problem......

Andy,

If the culprit was the positive battery cable to the starter, your mechanic could have tested and verify the source of the problem during a non-start incident. He was just guessing and had not done anything to verify his suspicion. Now that you have replaced the old battery cable with a new one, hope you got rid of the problem. And I wish you did. But I doubt it. Keep us posted.

Tony